Inspired by the chrysalis ask, how would instead of their s/o, they found the remains of the chrysalis and a moth monster, whivh is actually their s/o. How they discover this is up to you.
If I remember correctly, I did Underfell?
Huh. Uhh okay. Red is pissed at you for not telling him about your change and making him worry, but he’s also ?????????? He wants an explanation. Red still loves you and everything, just because you changed forms doesn’t mean he’s going to leave you, but he’s going to need a while to process. As for the monster part, he’s a monster too so he doesn’t care.
Before he realizes that the moth monster is you, he will fight. He refuses to accept that you’re the moth monster, not because he’s disgusted, but because he doesn’t want to accept the fact that would would keep such a big secret from him. When you calm him down, Fell, goes on like nothing has happened. To him, nothing has changed except your appearance.