
Either Eunho is really dumb and just doesn't know when to give up ... Or remarkably insightful with his persistence for hanging on ! Jaeha is an insecure and selfish brat ! LOL

Eunho is actually one of the most intelligent characters in BL/yaoi that seen.

He is one of those people where if you find them, hang on lol
The sh*t is fix'n to hit the fan now ! Machida-san ... slap him ... slap him hard, slap him NOW ! Make it clear that this is unacceptable ! And don't keep it a secret from Naruse. Have a discussion and tell him the truth. All of it. (You've been warned ! LOL )
This is what should happen, but for some reason I'm afraid it will be more like "Machida saying nothing to the guy, then she starts being made at Naruse and slaps him instead".