I often go out on weekends with a few friends of mine, we're all around 18-21 years old from Germany. One of them (lets name him L.) really is a chill guy. Me and my friends aren't really that good with girls in a romantic way, but we got some female mutual friends.
Now the deal is, every time our group is joined by a girl, L. behaves pretty "agressive" towards me and others. He's always trying to talk about himself in a good way while pushing us others down verbally. I should add we make fun of each other in a friendly, funny way all the time (as many guy-groups do) - nobody gets hurt and everyone, including the one made fun of at the moment, can laugh about the joke and/or roast the other one with a nice comeback. But when girls are around, L. does that to an extreme. He also always tries to push himself in the foreground.
I'm fairly skinny, hence I'm always called a leek ("Lauch" in German, a pretty common way to make fun of skinny people here in Germany). I don't really have a problem with that, but last weekend he wouldn't stop comparing me to thin objects literally all night (because a female friend of us was around). Furthermore, when one of us was speaking, he quickly got his phone out and showed us some memes to get the attention back on him, which was really annoying.
I now want to adress this behavior of his, make him aware of his behavior so that he hopefully stops/lessens it, but don't really know how.