Haikyuu!! Hanahaki Series
Disclaimer: Haikyuu!! (ハイキュー!!) belongs to Haruichi Furudate and this is a non profit series.
Haikyu!! is a Japanese shonen manga series written and illustrated by Haruichi Furudate. It's about boys who play volleyball, where the main character, Hinata Shoyou, is focus on becoming the strongest ace of Karasuno's team.
Hanahaki Disease (花吐き病 (Japanese)); is a fictional disease in which the victim coughs up flower petals when they suffer from one-sided love.
I choose to connect flowers with this characters because I feel that every and single one of the meanings is perfect for each boy. Their personalities are connected to flowers' meanings.