An Archer found in Celica's route. The rest is a quote from the Fire Emblem Wiki. 

"Leon has a pretty boy personality and sharp tongue, but he is an honest man that tells no lies. Leon has a nihilistic side, claiming he has desired to die in battle during his death quote in Gaiden; this is downplayed but still present in Echoes, where his death quote has him lament how his demise isn't as impressive as he thought it'd be.
In both versions of the game, Leon has a very close relationship to Valbar, describing him as his sworn brother and saying he will go wherever Valbar goes. In the remake, it is made clear Leon's attachment to Valbar is romantic, with Leon saying that women do not interest him and Valbar is all he needs, even if Valbar never notices Leon's love for him."

Leon's english voice is Lucien Dodge. https://youtu.be/6MsB4vZ0YnM?t=857