Suujin has a whole list for this type of manga here it is-
http://www.mangago.me/home/mangalist/717570/
╮( ̄▽ ̄)╭
19 DAYS VIBES
list is a collection of mangas/manhwas that have the same vibes with 19 days
• shounen ai
• bromance
• comedy
http://www.mangago.me/home/mangalist/717570/
Follow the list to be updated. And if you liked the mangas/manhwas I included, please do recommend. Enjoy~ (人 •ᴗ•)
Looking for manga/manwha/webtoon similar to 19 Days or Just Friends or 18 Unlimited