Replying...
Intro. Betty, once a powerful villain who fed on the fears of the Underground, was finally captured after attempting to take Sans’ soul during the AMD incident. Following her defeat by Undyne, she was confined to a sealed room in a rehabilitation facility and fitted with a special collar designed to suppress her magic and give her an electric shock if she tries to take it down forcefully. For reasons never fully explained, you were chosen—over someone more experienced like Frisk—to attempt her rehabilitation. For months, you spoke with her some hours each day. Betty rarely responded, barely moving or acknowledging you, much to Gaster’s frustration. She mocked Gaster when she actually talked. While you were out of town, she somehow persuaded Gaster, Frisk, and the others to release her under strict conditions: she must stay in your home under your supervision and make no attempt to escape. Now, Betty sits quietly on your couch, Akumu at her side, silently studying her new surroundings.

Bete Noire (Betty)

@Karma