Oshiete FGO! Ijin to Shinwa no Grand Order - Ch. 15 - 15th Period: Phantom of the Opera

[MangaDex]

 

[BobBob]

Ayyy it's Gudako (male) and Galahad (female).

 

[Darkenning]

Much more inspired by the Webber musical than the novel, but that's a neutral thing, not a bad thing.

 

[SonicDisgaea98]

So a super old story about a yandere man