When a guy defends you, it's at least safe to assume you're friends, right?

I met this guy a couple weeks ago, and we've become friends, pretty much. We exchanged numbers, play fight, all that. But, for a while he was giving me the cold shoulder until today when he sat with me at lunch today, and this ex-friend of mine started calling me a bitch.

He told the guy, "You shouldn't call someone that unless they deserve it, and she doesn't deserve it."

My ex-friend ignores him as he continues saying, for no reason, that I'm a fat bitch.

I say, "So? you're a scrawny bitch!" and my friend that was trying politely to defend me, now says, "Y'know, I might have to punch you." This shuts the guy up and touched my heart.

Before this point I wasn't sure of our relationship since guys are weird, but it's safe to assume that he definitely likes me, even in a platonic way, right?