My cousin and I made out for awhile.
Why did you kiss your cousin?
It seemed like it would be fun.
Even if you thought it was fun, doing sexual things with people related to you is wrong. If you continue to do it and your family finds out, there will be a  lot of awkwardness and tension for everyone involved. It may lead you to never seeing some of your family again.
I don't really care.
Don't you want a good relationship with your family? It would be best to avoid spending time alone with your cousin so you won't get in that situation again.