She is and she explains

You looked at her in shock. "You... l-love me?"

She nods while also blushing. "This is some kind of dream right?"

"I guess I should explain." Selsa stands up and snaps her fingers and suddenly she is dressed as a sexy school teacher with glasses, a ruler, and a chalkboard. "As you know, I de-aged myself for you last night. When that happend though something went wrong."

"So, you really lost your memory last night?" She nods.

"When I turned back to normal, I lost my original memory of my first time and my first kiss."

You were surprised. "So, you're a different person now? Is the old Selsa gone?"

"Yes and no." She points her ruler at the blackboard that now has (surprisingly detailed) drawings of her young and curent form. "While I lost my original first kiss and my first time, I still have the original memories outside of those two."

You try to understand. "So you're the same Selsa but your feelings for me are whats different."

Selsa smiles and nods. "Yes, while I might act like my old self at times, my love for you will always be true."

Everything you heard is so overwhelming. "I-I need some air" you quickly get out of bed but Selsa grabs your arm and hugs you.

"I know I dont deserve it, but all I want is your love. I'll get rid of my Sara persona, I wont fuck around with other guys, I'll do anything." She looks up at you and you see her crying. "Please..."