rub up against

verb4

1. •
   To touch something with one's body.

   • She accidentally rubbed up against the painted door and got green paint on her blouse.
2. •
   To touch another person with one's body in a sexually stimulating manner.

   • Now men, I have rubbed up against a few men in my time, but women? — 1994
3. •
   To touch a person's body in a friendly manner, seeking attention. (of animals)

   • Tibbles the cat rubbed up against my leg, asking for a piece of my cheese.
4. •
   To come into conflict with someone or something.