That's not my baby to rock
when a situation arises that is not your problem to address or remedy
Friend 1: (late at night) Tito just got dumped and needs a place to stay for a few nights.
Friend 2: That's not my baby to rock. Sucka.
Or
G/F: I didn't cum
B/F: That's not my baby to rock.
Friend 2: That's not my baby to rock. Sucka.
Or
G/F: I didn't cum
B/F: That's not my baby to rock.