Dog day afternoon

So yesterday afternoon I get a call from my friend L....she tells me that a friend of hers has a friend who is giving away(FREE) full bred boxer puppies and she is getting one! Very cool I say, let me know when you get him I wanna see him(I love dogs!)! SO later on last night I get a call from L...she tells me a few things 1. puppy is NOT a pure bred boxer 2.puppy owners are strange and wanted her to just take him or they were gonna take him to the pound cause he was the last left and is 9 weeks old 3.he is way too skinny and she thinks all these dogs live full time in a HOT garage .She tells me she told the people she would be back tomorrow, and that she can't keep this dog, cause she was going to live with a roomate but now her situation is unclear and she just doesn't know what to do, but she can't leave him there. So, I(in my can't kill a fly mind) say....omg...just get him...we will find him a home, he can stay at my house till then. So she gets him today,we trade him off, I bring him home....and well....my husband (who was SUPER against it) tells me after a few hours, let's just keep him. He is cute, and he fits in. So...at this point I think he is here to stay....we have named him Hewy. Now I just gotta get some weight on him...get him to the vet...and get him potty trained which he seems to be doing remarkably well with...the previous people must have at least done that. But.....WHAT is he??? ANy ideas what breed he is? I know he for sure has boxer in him...but he isn't pure bred. It doesn't matter, but I would love to hear your opinions!