Bunfuck

Bunfuck is a hair-sex kink involving using a partner’s hair bun as a sex object or sex toy, typically by thrusting into it, grinding against it, or rubbing against the tightly tied bun as though it were a body part meant for penetration. People with a hair fetish (trichophilia) might be into a bunfuck. It also overlaps with Dom/sub dynamics, teasing, objectification, and playful roughness.