Translation of tranquilizar

His name was Leo and he would become a good friend of mine during the next two weeks. He had a lovely girlfriend where he stayed during my visit. Basically, I slept in his place when he was away.
Let me talk about nicer things in this email. In the last mail we spoke about the poems that we have read in our last spring break. We are not of the kind who love partying all night. We came to relax.
The room had around 4 square meters and the bathroom and shower were tiny. I was not content about that, as we could have stayed in a much better hotel for less. But we had made reservations in advance anyway.