Games like Extra Case: My Girlfriends Secrets
Games like Extra Case: My Girlfriends Secrets include Doki Doki Literature Club Plus!, Urban Myth Dissolution Center, Until Then, Slay the Princess — The Pristine Cut, and The Hungry Lamb: Traveling in the Late Ming Dynasty. We matched them by the tags players give Extra Case: My Girlfriends Secrets on Steam (Psychological Horror, Visual Novel, Romance, Mystery, and Lovecraftian): closest matches first, and among equally close ones the better-known games.

Doki Doki Literature Club Plus!
Shared: Psychological Horror · Visual Novel · Dating Sim

Urban Myth Dissolution Center
Shared: Psychological Horror · Visual Novel · Mystery

Until Then
Shared: Visual Novel · Romance · Mystery

Slay the Princess — The Pristine Cut
Shared: Visual Novel · Psychological Horror · Romance

The Hungry Lamb: Traveling in the Late Ming Dynasty
Shared: Visual Novel · Dating Sim · Story Rich

Scarlet Hollow
Shared: Visual Novel · Psychological Horror · Dating Sim

Danganronpa: Trigger Happy Havoc
Shared: Visual Novel · Mystery · Psychological Horror

DREDGE
Shared: Lovecraftian · Exploration · Psychological Horror

OMORI
Shared: Psychological Horror · Story Rich · Indie

Raging Loop
Shared: Visual Novel · Psychological Horror · Mystery

Danganronpa 2: Goodbye Despair
Shared: Visual Novel · Mystery · Psychological Horror

LoveChoice
Shared: Romance · Visual Novel · Dating Sim

Impostor Factory
Shared: Story Rich · Adventure · Psychological Horror

Lay a Beauty to Rest: The Darkness Peach Blossom Spring
Shared: Visual Novel · Mystery · Adventure

The House in Fata Morgana
Shared: Visual Novel · Psychological Horror · Mystery

Firework
Shared: Psychological Horror · Mystery · Visual Novel

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

Sucker for Love: First Date
Shared: Romance · Psychological Horror · Lovecraftian

The Weeping Swan: Ten Days of the City's Fall
Shared: Visual Novel · Romance · Psychological Horror

Milk inside a bag of milk inside a bag of milk
Shared: Psychological Horror · Visual Novel · Horror

Dagon: by H. P. Lovecraft
Shared: Visual Novel · Lovecraftian · Psychological Horror

ATRI -My Dear Moments-
Shared: Visual Novel · Romance · Dating Sim

The NOexistenceN of you AND me
Shared: Psychological Horror · Visual Novel · Story Rich

YOU and ME and HER: A Love Story
Shared: Psychological Horror · Visual Novel · Romance