Hi! Does anyone know (this is the only part of it that I can remember though I don't even ...

Hi! Does anyone know (this is the only part of it that I can remember though I don't even recall their faces...) a yaoi where at one moment the seme is carrying the uke on his back and I don't know why (drugs or...?) but the uke is horny and the seme starts running and the uke gets even more aroused because his "thing" is rubbing against the seme's back as he runs. I know it makes me sound like a pervert but it's been bothering me and I want to know what it is! ╮(￣▽￣)╭
Thanks!