How to make a second minecraft without buying it again?

I share a minecraft with my brother. He bought the game and it's on the family computer. I'm getting tired of going on my brothers account with a name that doesn't fit me. Is anyone sure of a way that I don't have to buy minecraft? And I need a full membership, not that demo stuff and all.

Lol for magic luncher

There should be an update that lets you change your name coming up, but there's nothing for sure about when it is coming out. The only possible thing before that is buying your own copy.

There's not without re-buying an account. It is your account, and hence your user name, that determines whether you can play, not that you have downloaded the software.