Hey guys a plate that I wanted a LTR with is going on a date with a guy she met in a club that gamed her through Twitter and she told me ' dont kill me but were going on a date'

Obviously no longer LTR material and I obviously told her to enjoy but what should my plan of action be?

Her date is after tomorrow. She's coming over tomorrow. I'm thinking be normal and hook up tomorrow and when she texts to talk after tomorrow simply tell her she has a date with another guy so she's his for the day

Thoughts?