Sexuality dysphoria ?

well it depends. Watch for signs, maybe he's also gay LOL

 

then just tell him, there's nothing bad that's going to happen. In fact, one of my friend also says that he's gay to me and I don't feel anything weird had happened

 

I think that's not a very wise thing to guarantee.... you don't know what will happen. There is still a lot of discrimination against gay people in this world. I believe honesty is best, especially if you're searching for support from someone you care about, but I would be prepared for the possibility that he might not take it well. Because unfortunately you really don't know.

I told my best friend that I'm attracted to girls and used to have a crush on her, and thankfully it didn't make anything weird between us. But I was prepared for the fact that it could have. Hopefully your friend takes it well and you get the support and guidance that you need.

 

You need a someone to support you being gay? Seems like something you'd keep to yourself to be honest.