 If you liked
Adekan
|
 ...then you might like
Kuutei Kaiko Toshi
|
If we go by plot and characters than these manga are absolutely different from each other and there is nothing similar here but the fact that the hero is entrusted to take care of the other protagonist which in Adekan is a boy and in KKT is a girl.
For those who appreciate a detailed breath taking artwork in manga than we can talk about similarities: these two provide scenery-porn, unusual beautiful art that makes you stare at each page like if you're in a black and white painting.
So if you like one...you might want to try the other!