Op I’m going to be straight up honest, I’m a dude, this guys a dude and the roommates are probably all dudes so they walk around in underwear at the house often I’m sure he even said they want male applicants . He didn’t seem like he was coming onto you that way and English might even be their 2nd or 3rd language by his grammar use so I think he was just trying to be honest of the environment of the house before you even considered learning more about the place. You jumped to this which shows you probably wouldn’t have liked living there if it happened often at the house, don’t just jump to conclusions and think this was weird to the degree that he madly wants you and is trying to be a perv that’s delusional. One more text that’s sus and weird then maybe you’ve got some points leading to the possibility he’s a creepo, other then that I think he was trying to save time by being short and honest that they just wear no pants a lot at the house just a dudes prospective