I'm going to get involved in someone else's business.
What sense does it make to involve yourself in another person's business?
The person has lots of friends, so maybe I can benefit from those relationships.
It's not good to misrepresent yourself for purely predatory reasons. You should mind your own business.
I'm trying to improve my life.
You would be using your friend if this was what motivated you to get into their business. You can ask them if they need any help, however assuming that they want you around all the time is an invasion of privacy.