she's trying to snare him further into her webwell, she is attempting to appear mostly normal to MC, tho idk what is necessarily appealing versus it being some wish fulfillment self insert, even with the other woman being interested in him (tho i guess the author likes writing these kinda chara archetypes, maybe one day we'll see a role reversal with them having a male yandere and the femmc being ok with it/into it lol)