@krisdreemurr There isn't actually that much that canonically deals with aromanticism and asexuality. Usually the main content is about other LGBT themes and asexuality is somewhat present. Or they have characters that are not interested in love over the course of the series, but nothing is explicitly stated, except perhaps by word of god. That's how Luffy became an ace icon.
Miss Kiryu Doesn't Understand Love. (https://mangadex.org/title/20034/kiryuu-sensei-wa-renai-ga-wakaranai) is one of my favorites, but it hasn't been translated in a while.
Shimanami Tasogare (https://mangadex.org/title/15976/shimanami-tasogare) of course
Kanojo ni Naritai Kimi to Boku (https://mangadex.org/title/34693/kanojo-ni-naritai-kimi-to-boku) a later minor character is ace
I hear there's an aro character in Bloom Into You, but that series is on my backburner right now so I haven't read that far yet