There are two routes that can be found in Omori. The true route and the hikikomori route.
The True Route, otherwise known as the "Sunny" route, is the route where Sunny, under Kel's urging, chooses to go outside all three days before he moves. He reconnects with his old friends, and ultimately confronts the truth he desperately attempted to suppress for four years.
All 5 endings can be obtained on this route.
Should Sunny choose to go outside on Three Days Left, but ignore Kel and go back to bed on Two Days Left, the True Route will be aborted and replaced with an Hikikomori Route with minor differences.
Sunny still acquires the Photo Album on the first day. Checking it on One Day Left will reveal that Sunny has scribbled over every photo once again in black marker.
The Hikikomori Route, otherwise known as the "Omori" route, is the route where Sunny ignores Kel and chooses to stay inside for all three days prior to him moving. Sunny manages to suppress the truth once more, at the cost of completely losing himself.
Only two endings can be obtained on this route, all variants of neutral endings.
There are many differences
- An extended Headspace, with the ability to resurface Humphrey, new areas such as Snowglobe Mountain, and new sidequests.
- An extended, non-linear Black Space that can be revisited at any point after defeating certain bosses, and freely explored.
- Multiple enemies and bosses are buffed, with better rewards.
- The ability to 'lose' Hangman by collecting every letter, required to access The Abyss.
- New powerful skills for Omori, based on Sunny's fears.