@lainfec Seinen and Shojo are demographics; young adult men and young girls respectively. Just cuz this story is a romance doesn’t disqualify it from being in a Seinen magazine. Like certain types of romance stories can be common for different demographics but I don’t really see anything out of the ordinary for a Seinen romance.
Hell if you look at Weekly Young Jump (Seinen), it has four romance stories.
Kaguya-sama
Kubo-san
Kowloon (by the author of this manga)
100 Girlfriends
Each one very different from one another and bring variety to a weekly magazine.
@Emeraldfiree
I spoke too soon here, Her motivations get explored big time in the later chapters LOL. My bad, I just felt at this point that her character was too shallow to be enjoyed by the audience but it becomes a major plot point later. Thanks for the info tho, I learnt something new.