Games like 骸心 Mainbody
Games like 骸心 Mainbody include OMORI, SOMA, Sally Face - Episode One, The Test, and No, I'm not a Human. We matched them by the tags players give 骸心 Mainbody on Steam (Psychological Horror, Emotional, Story Rich, Exploration, and Multiple Endings): closest matches first, and among equally close ones the better-known games.

OMORI
Shared: Psychological Horror · Story Rich · Multiple Endings

SOMA
Shared: Psychological Horror · Story Rich · Horror

Sally Face - Episode One
Shared: Psychological Horror · Story Rich · Horror

The Test
Shared: Story Rich · Psychological Horror · Choose Your Own Adventure

No, I'm not a Human
Shared: Psychological Horror · Story Rich · Horror

The Coffin of Andy and Leyley
Shared: Story Rich · Psychological Horror · Multiple Endings

Darkwood
Shared: Psychological Horror · Horror · Exploration

SILENT HILL 2
Shared: Psychological Horror · Story Rich · Horror

Slay the Princess — The Pristine Cut
Shared: Psychological Horror · Story Rich · Choose Your Own Adventure

Mouthwashing
Shared: Psychological Horror · Story Rich · Horror

The Casting of Frank Stone™
Shared: Multiple Endings · Story Rich · Psychological Horror

Tiny Bunny
Shared: Story Rich · Psychological Horror · Horror

What Remains of Edith Finch
Shared: Story Rich · Exploration · Atmospheric

Ib
Shared: Story Rich · Psychological Horror · Horror

The Cat Lady
Shared: Story Rich · Psychological Horror · Horror

MiSide
Shared: Psychological Horror · Story Rich · Horror

Detention
Shared: Psychological Horror · Story Rich · Horror

Fran Bow
Shared: Psychological Horror · Story Rich · Horror

Detroit: Become Human
Shared: Story Rich · Multiple Endings · Emotional

Dagon: by H. P. Lovecraft
Shared: Psychological Horror · Story Rich · Horror

Milk outside a bag of milk outside a bag of milk
Shared: Psychological Horror · Story Rich · Multiple Endings

Little Nightmares II
Shared: Psychological Horror · Horror · Story Rich

Milk inside a bag of milk inside a bag of milk
Shared: Psychological Horror · Horror · Abstract

Layers of Fear (2016)
Shared: Psychological Horror · Horror · Story Rich