share chapstick

A phrase used to imply one's desire to touch lips with another persons' lips.

Mario looked at Dirty Di's lips longingly and asked, "So... uh, you wanna share chapstick or what?"

Sharing chapstick

When the girl rimming you and the girl blowing you switch positions they're sharing chapstick.

Oh dude, see Jill and Lisa over there, I hear they love sharing chapstick, we should invite them.