|WARNING: This article contains spoilers for the main story of OMORI.|
Sunny is default name of the player character and silent main protagonist in OMORI. Sunny is controlled during all real-world segments of the game.
Sunny wears a white-collared shirt with a blue vest over it. He wears beige shorts, white socks, and black shoes.
Sunny has been described as an extremely shy, but kind boy. Multiple characters, most notably Basil and Aubrey, describe him as a "really good listener" and as someone who "always had time" for his friends, but also as someone who dislikes "taking the lead."
By the time OMORI begins proper, Sunny is borderline neurotic, and almost completely detached from reality, as shown through incidents such as regularly hallucinating aspects of Headspace even in reality, repeatedly having to be reminded by Kel about things as simple as not walking into the street, and showing no reservations over carrying a potentially lethal weapon around and even attacking with it, to Kel's shock.
Closely examining his behavior in both the real world and as Omori in Headspace paints a broader image of his personality. Sunny appears to have anger issues; he has a very short temper (something as small as a fly buzzing near his ear is enough to anger him), and this anger tends to express itself through dramatic, sometimes violent outbursts. This anger critically leads to an incident where, frustrated over his lack of progress with violin practice, he threw his violin down the stairs in a fit of rage, smashing it, followed shortly after by fatally shoving Mari away from him during a heated argument, something the Truth photo album describes as him "losing all sense". Notably, in battle, his Angry portrait depicts an intense amount of emotion, more than every other character's, even Omori's. Sunny appears to additionally suffer from anxiety, and had learnt to Calm Down, Focus, and Persist in order to help him cope with his anxiety and phobias, although he has forgotten these by the time of the game's events and needs to be reminded.
Sunny appears to be somewhat judgmental and snarky: Omori's skills such as Mock, Exploit, and Shun encourage him to take advantage of other's emotions, and Omori's commentary in Foe Facts! often contains snide jokes and commentary towards the many enemies he faces. Sunny appears to have a rather sharp sense of humor, going by the many quips he makes, both as Omori in Headspace and in reality.
He also demonstrates remarkably high intelligence: Despite having dropped out of school when he was twelve years old and technically lacking most formal education, he appears to have functional knowledge of advanced concepts such as calculating standard deviation of statistics and can successfully tutor two children in two different subjects that he likely hadn't been properly taught.
He is additionally shown to be very helpful, being able to work for multiple people and shops throughout Faraway Town, and optionally helping others with their errands and requests with little to no payment, showing no objections. However, it's suggested that this may instead be related to his extremely low self-esteem: Omori comments on this during the final battle, suggesting that he feels himself to be "useless... less than useless [...] sick," and as someone who doesn't "deserve to live."
Sunny was born to unnamed parents on July 20th, being approximately 16 years old during the events of the game. He had an older sister named Mari and presumably has lived in Faraway Town since his childhood.
In his youth, Sunny used to play the violin, but stopped at some point. Noticing how much time Sunny spent listening to Mari practice on her piano, Sunny's friends ultimately saved up to purchase him a new violin, allowing him to reattend his lessons and spend more time with Mari. While he initially enjoyed the lessons, he found himself growing increasingly frustrated over his sister's perfectionism, his lack of progress in practicing, and his lessons interfering in the time he spent with his friends. He frequently played with his neighbors Kel, Hero, Aubrey, and Basil, the latter of which was described as being his best friend. Basil's photo album shows the group being extremely close knit: They went to school together, they celebrated each other's birthdays, and they even coordinated to build a treehouse in Sunny's backyard.
Sunny's frustrations about violin practice and his sister's perfectionism reach a boiling point the night before a duet recital they had planned: Under pressure from his sister and in pain from constantly practicing, coupled with his general insecurities about "not being good enough", he ultimately hurls his violin down the flight of stairs in a fit of rage, breaking it. A furious Mari confronted him and began yelling at him, although Sunny was disorientated enough that he "couldn't understand" the argument. Sunny attempts to leave by going down the stairs, but Mari physically blocks his path, saying they "aren't done talking," prompting Sunny to attempt to push her out of the way. This push knocks her backwards, and she tumbles down the staircase, instantly killing her. In complete disbelief over his actions and in denial about Mari's death, Sunny attempts to drag her upstairs and tuck her into bed, justifying her lack of response as her "needing rest," before breaking down completely once the truth dawns upon him. The unused Truth album text suggests that this is the exact moment White Space was created, as a way of disassociating from the reality of his actions.
At some point, Basil enters their house and is mortified to discover Sunny sobbing over Mari's corpse. Refusing to believe that his best friend could kill his own sister, even by accident, Basil justifies it by saying "Something behind [Sunny]" did it and is attempting to frame him for Mari's death. He suggests to Sunny that they protect him by staging Mari's death as a suicide to shield him from the consequences, assuring him that "everything will be okay."
Sunny heavily disassociates through the process, barely registering anything after dragging Mari's body outside up until Basil ties a noose and hangs her corpse on the tree in Sunny's backyard, at which point he suddenly is hit with the realization that "all of this is real." As they return inside, Basil suddenly stops and looks back at Mari's corpse in horror. Sunny turns and sees one of Mari's eyes staring back at them, traumatizing the two boys and creating the form of Something.
Sunny afterwards completely disconnected from the outside world, becoming a hikikomori. He eventually stopped going to school, and began spending most of his time sleeping, escaping into his dreams, where nothing had happened, Mari was still alive, and he still regularly hung out with his friends. This eventually escalated into his complete refusal to leave his house for the next four years.
The beginning of the game takes place four years after Mari's death and over the course of three days, after which Sunny will be moving to a new town. Through the player's choices, the game has multiple endings and two specific routes that can be taken.
Night 1 occurs regardless of what route the player chooses. Following Basil's disappearance in Headspace, Omori stabs himself in White Space, which, in reality, causes Sunny to wake up in the middle of the night, hungry. While attempting to get food from the kitchen, he has to conquer his fear of heights to go down the stairs; which is where he remembers how to use the skill Calm Down. Sunny then heats up the steak his mother left him and eats it. However, his stomach "doesn't agree" with the meal, and he heads to the bathroom to vomit into the toilet. Afterward, the sound of knocking prompts Sunny to check the front door, where Mari can be heard asking Sunny to let her in. Sunny is given a choice to either answer the door, or leave it closed. He is briefly scared by Hellmari should he open it. After choosing either option, the night ends with Sunny going back to bed and re-entering White Space.
The true route allows for the Good or Bad endings to be reached, but the neutral endings can also occur depending on the player's choices.
Sunny wakes up in the morning to someone knocking on the front door. When he opens the door, Kel is on the other side. Going outside then gives Sunny the opportunity to see his old friends and overall be more active within his waking life. The day goes on as Sunny and Kel learn that Basil's Photo Album was stolen by Aubrey. They confront her, where she reveals that she felt betrayed by all of them after Mari's death and believes she is keeping the photo album safe. After this, Sunny and Kel see her throw away the photo album and are able to retrieve it. They take it back to Basil and eat dinner at Basil's House. Basil's behavior becomes increasingly strange, leading to him running to the bathroom. When Sunny checks on him, he is terrified and mentions also being able to see Something. The player is then forced to make Sunny leave, despite Basil's pleas for him to stay. Sunny goes home and fights Something, overcoming his fear of spiders and learning the skill Focus.
The days in the Hikikomori route are considerably shorter, as they only consist of Sunny doing his chores and then facing the Something that corresponds with a fear blocking out sections of Headspace. This route prevents the completion of the Good or Bad endings, and only allows for the Neutral endings.
During the first day, Sunny must choose not to answer the door in order to start the Hikikomori route. From there he will sweep the house, afterward taking a nap and waking up at night. He will come across Something again, this time taking the form of a mutated spider. Fighting Something allows Sunny to gain the skill Focus, and gets rid of his fear of spiders.
On Day 2, Sunny is tasked with doing the dishes. Afterward, he takes a bath and slowly sinks down. Upon resurfacing, his house will be completely flooded. Following Mari's ghost down the stairs prompts him to fight Something, this time looking like underwater plants/tentacles. This fight allows Sunny to learn Persist.
On the last day, Sunny will be stalked by Something throughout his house no matter where he goes. The last chore involves sorting through Sunny's old belongings, placing them into different boxes. From there, the player can choose either to go back to Headspace or have Sunny sleep until Moving Day. Either way, after he falls asleep, his body is taken over by Omori. Following this, he will see himself as Omori should he check his bathroom mirror.
On Moving Day, there are two possible endings that can be achieved. If Sunny goes to sleep, he will wake up and leave the house, ending with the credits rolling and the sound of sirens, implying that Basil, without Sunny's intervention, has killed himself. Alternatively, Sunny can instead choose to stab himself by opening the menu and selecting Stab, prompting him to commit suicide.
|Guard||Acts first, reducing damage taken by 50% for 1 turn. No Cost.||Default|
|Calm down||Acts first, removing all emotions and recovering Heart equal to half of Sunny's max Heart. No Cost.||Encountering Something in the Dark|
|Focus||Next attack deals more damage. No Cost.||Encountering Something in the Walls|
|Persist||Heart cannot reach 0. No Cost.||Encountering Something in the Water|
|Overcome||Gather all your courage. No Cost.||Encountering Something|
|Allegro||Attack 3 times. Costs 19 Juice.||Encountering Omori|
|Encore||Your Juice will not fall for 3 turns. Costs 0 Juice.||Encountering Omori|
|Cherish||Heal your wounds and come back stronger. Costs 0 Juice.||Encountering Omori|
Afraid, console exclusive to Boss Rush
- Sunny is the only character to have two different Neutral battle portraits. His eyes will be open during normal battles, while his eyes will be closed during the hallucinatory battles against Something in the Dark, Something in the Walls, Something in the Water, Something, and Omori.
- The same portrait is also used if he falls unconscious.
- In battle, Sunny cannot become Happy under any circumstances; even if cheats are used to alter the party's emotions, he is completely immune to becoming Happy. He is the only character in both reality and Headspace where this is the case.
- In fact, Sunny's sprite sheet does not even have portrait frames for him being Happy.
- Uniquely, he also cannot become Depressed or Enraged, whereas all other party members in reality can with cheats.
- Omocat reveals that Sunny's mannerisms and awkwardness are based on their own from high school, meanwhile his hair and clothing from a friend from elementary. 
- The clothing Sunny, Mari and Basil wear was the uniform Omocat wore in school from elementary to high school.
- Kel: You shouldn't walk in the street, Sunny! That's dangerous!
- Kel: You shouldn't be carrying things around like this, Sunny... That's dangerous!
- Photo of a Murder: You lose all sense and push her down the staircase.
- Aubrey: In the few months after Mari died... everything changed so fast. Sunny and Basil became more closed off... [...] After Sunny stopped coming to school...
- Photo of an Argument - Mari was yelling at you. You couldn't understand what she was saying. She didn't understand you at all... She didn't understand that you just weren't good enough. The only thing you hold onto was your anger. This pain... was it her fault?
- Photo of Hopelessness - Everything appears dark. The shadows slither around you. You don't understand what is happening... Your head starts to feel fuzzy... You sink into a crevice in your mind... an empty white room.
- Photo of Support - Your shoulders feel heavy. A familiar voice whispers something unspeakable. Your eyes widen. It tells you to follow its lead. It says... it's the only way out... It says... that everything will be okay.
- Photo of Something - Suddenly, Basil stops. You look up at his eyes... but this time, they’re wide awake, staring at Something. You turn your eyes toward it as well, though you wish you didn’t. An eye meets yours. Your heart sinks into your stomach. You shouldn’t have looked back... You just... shouldn’t... have looked...