Kylie Jenner — Heating Up with Lil Twist

15-year-old Kylie Jenner is playing the field — just a week after hitting up a movie with Will Smith“s son Jaden, things got SO HOT between her and Justin Bieber“s friend Lil Twist … they had to cool off with frozen yogurt.

While Jaden was out doing his own thing, Kylie and Twist got together yesterday in West Hollywood for some Pinkberry … A WELL-KNOWN APHRODISIAC!!!

Funny, Twist has a terrible track record behind the wheel of Bieber”s cars — example 1, example 2, example 3 — but for some reason, Kylie still let him drive her around.