My 17 year old step brother asked me i he could touch my feet?

That is really weird... If it makes you uncomfortable tell him and if he still doesn't stop then tell somebody else its as simple as that. You shouldn't let people do things to you that you don't want them to do, even if they cry, it doesn't matter. If you don't like it, or want it to happen then they have to accept and respect that. No means no regardless of anything else.