NeKiA's manga / #Assassin(18)

https://www.anime-planet.com/manga/cage

3 Hana to Ryuu > Sessa Takuma > Kizuna > Gun and Heaven. 〚 3 years after Kizuna, the tashiro x j.b. couple settled down in some foreign country. 〛 Assassin couple returns. The many-faced, #half-japanese tashiro roy and his mentor and older lover j.b and their dangerous life together. Separate story, no appearance of prequel main cast. @CH. 6: shu hua cameo (the brat who chases j.b from kizuna).

https://comic.pixiv.net/works/4416

https://www.justoon.co.kr/content/home/06nb0071320e