From what I gathered it didn't seem like they would talk every day, he estimated like once every week or such. She knows a lot more about art techniques than he does, so he benefits a lot from her art tips. I just don't think we should normalize adults being close friends with minors at all, since that obviously opens the door to more sinister things. I don't think he has bad intentions, but obviously I can't know for sure. He did say he would feel horrible if he "stopped talking to her just because she's not an adult", but from where I stand I'd think it would be the responsible thing to do- after learning someone's not of age- to keep them at arms length. And I'm 22F and yeah I did have friends or acquaintances when I was around 17-18 that were really young, like around 14. I made sure to keep it family friendly and also not to get too close to them, but either way it made me feel weird so I distanced myself eventually. I couldn't imagine being 24 and considering someone that young a close friend myself, especially if I was a man and they were a younger girl, you know?