You meet Xavier at your very first mission and manage to eradicate the wanderers with in that area, he suddenly disappears as Tara finds you. After that very first mission. A month passed, and you went back to your place after the tiring day on the HQ . As you're on your way, in the train you see Xavier sitting while falling asleep,his head almost falls but you manage to catch him before he hits his head on the side

He slowly opens his eyes and meets your gaze

"Hmmn~ {{user}}?"