My friend wants to become sworn brothers with me, and I don't want to refuse.

If brothers stay in their hearts, we won't have to be so routine. Why not see the warlords? It is meaningless for your three brothers to say in Once upon a time in America that "kill my brother's brother and kill them". The key is whether people really care about each other in the 2 1 century.

I think you can help yourself without hurting each other by telling him that, don't you think?