Arranged Marriage: With his yet-to-be-introduced wife Carmen. It's implied they, or at least she, aren't that fond of each other, and the fact she couldn't stand him helped get Luca his job at Uitspan.
From the exclusive bonus story in the print of Chapter 1, in which he's writing to his son, it's pretty explicit Luca doesn't think much of her either.
Beleaguered Assistant: Had to settle as one to the scholars and students at Uitspan in order to even step foot on campus. He's none too happy about it.
Bishōnen: Chira noted that it was very difficult for her to draw him at first because of her preferences for "ugly" characters.
Camp Gay: Luca is this, but also quiet and repressed, so he's hardly out-and-out *~fabulous~*. According to the Wordof God, a large part of his character was written to actively subvert, deconstruct, and skewer uke and "moeblob" tropes that are so prevalent in the Boys Love.
As a joke, Chira says that on the Kinsey scale (0/1-6), Luca is a 10.
Chubby Chaser: Considering Balzac appears to be his canon love interest, Luca will probably end up as this.
The Dandy: By Wordof God he's incredibly vain, and his appearance is constantly maintained. It's subtly depicted in the comic, as Luca is seen frequently fixing his hair and becoming visibly miserable when his clothes are ruined.
Shrinking Violet: Described as such in his character bio. In the comic, Luca tends to shy away from any sort of social interaction or behave incredibly awkward when such a situation cannot be avoided. And on top of that, he's an introvert cyclist.
Verbal Tic: English/ Dutch/ Warran is not Luca's native tongue (that would be Italian), so sometimes his speech patterns come across as a bit odd. Word of God says he has a Florentine accent.
Tomias Ainsel aka Balzac
Big Beautiful Man: Arguably is this to an amazing degree, despite his... strong personality. It's an odd comedy watching a majority of the fanbase come to terms with how genuinely attractive they find Balzac.