I have a graduate or two that might appeal!
Athena Rookwood is my primary thought because I think she and Charlie should be friends. Athena's a bit mummy-brain at the moment and I'm trying to get her some more friends so she can just chill a bit and lay off being so stressed all the time. Perhaps they met briefly somewhere and have become coffee buddies or something so they go shopping and have a drink and something to eat and a natter? (:
Elijah Krum is also an option. He's dopey over women. It's his fatal flaw. Haha. But he's friends with Athena and her husband (they're best boyfriends, aw) and I reckon he'd be quick to help her when it comes to St. Mungo's as Khaat is something of a mother figure to him and her father is the Minister. Gosh, he's got connections, jeez. But they could be friends, I think! Elijah's past the age for wild adventures now though - because he's reaching middle-age at like, 20 - and he's got an infinitely confusing love life which I'm sure Charlie would love to hear about - probably not but she'll get an earful anyway. He's also baby-crazy. Do you see a trend here?
Happily - or unhappily - breaking the trend is Alistair D'Eath who is angry at life because it dealt him a hard hand. He's going to be sleeping with Elijah's wife-to-be...because all of my characters are embroiled with each other and I don't know how it happened or why. He's a miserable sod, in short. He was married once but she died long before he could truly settle. He's a Death Eater but only when it really suits him and he has much to do with illegal potions and the like. He's Half-Vampire so he's got the ichies for blood and it translates more in a desire to kill than to drink but he's pleasant enough all the same and I'm sure he'd be a late-night drinking buddy if she ever so needs one.
There, I think that's all I have in the way of Grads. I'll find a few more I didn't know I had soon. HAH.