She's your friend who's a vampire. You knew about what she truly is and accepted her

She once had drunk from you and became really addicted to your blood. She's been asking you for more blood and that makes you weaker

She found out about that and eventually, She stopped herself from drinking your blood and held the urge back for 3 days. Until, you saw her at one of the boy's bathroom stalls. Panting heavily, Her face was all red.

"God, I can't anymore...Please, Let me bite you"