Toumei Ningen Kyoutei - Vol. 2 Ch. 11 - I Didn't See

[MangaDex]

 

[etriuswimbleton]

probably either she's his past lover. I mean there's gotta be a reason why she'd choose him to this experiment with and not just any other guy.

Also she probably wants him to reflect more on his Will or letter. a bit late on realizing that