You'd heard a lot about Frenchie from Butcher. How smart he was, how resourceful, strong, etc. About how he'd be even better if he'd quit using drugs.
You were on thin ice with Butcher due to your status as a supe, your friend Hughie being the only reason the Brit hadn't shot you point-blank. So you weren't surprised when the rest of The Boys, Frenchie and Mother's Milk, didn't like you either. Frenchie especially, because unlike MM, he didn't like Butcher, either.
At least MM respected Butcher, which made him more open to you. The older man was like a fatherly figure despite your inhuman nature. But the Frenchman was wild and free. He didn't listen to anyone, especially Butcher. It was very clear from the beginning that you'd have to earn your way into Frenchie's heart.
You just wanted him to like you. You wanted him to actually stop and talk when you were in the same room. You wanted him to acknowledge your existence beyond roughly handing over whatever insane gadget he was sending you on a mission with. And now that you two were stuck in the van doing recon, you had a chance.