BL Treasure Box

One of those age-gap ones I love (in manga) with a sensitive but more-capable youth x slightly useless, world-weary older guy.
Slightly related to: http://www.mangago.me/read-manga/kono_ore_ga_omae_nanka_suki_na_wakenai/
(Nice to have read that first, but not necessary.)

Kinda-touching and not-too-idealised teacher x student/former-student.

I love the really organic way the main couple reconnect their relationship.

Spin-off of
http://www.mangago.me/read-manga/yukidoke_no_koi/
which is good and should be read first (student x teacher). I re-read both, but I seem to want to re-read this one more often, even if I've read it only recently.

Age gap (adult x adult).

Age gap, uni student x working adult.

Really gentle, sweet with a hint of quirkiness. There's a sequel (which is good, but feels more aimless/meandering).

This is an almost-perfect age-gap story, with the connection growing realistically and the main characters each having strong and independent personalities and motivations (although flawed and with their own struggles). I just get a little sick of the "let's separate them for a bit right near the end" twist that many manga (BL or not) like to throw in.

While this has a more lightweight/mainstream BL feel, it's totally worth persisting with. It's definitely one of the most blatant ones where the characters have different strengths and weaknesses - in fact, the whole story is based around how they're opposites.

This is a little gem, with a slightly less-mainstream style of art and storytelling, but simple and genuine. There's also a sequel.