I need help please

Hi everyone, im looking for a yaoi manga which I believe is written by Mizukami Shin, the author of koutetsu no daitenshi(If you know it lol). I've been looking at all of his/her (sorry idk the gender) work and I haven't found the story I was looking for, so it goes like this.
It's a ninja sort of setting where the uke is a pupil of the seme, the uke had always liked the seme but he never really had the courage to confess, so one day, the master of the village asked the seme to kill his previous master because he was seen as a traitor to the village, the uke thought that the seme and his previous master had some sort of relationship so instead he volunteered to kill the traitor on his own. Soon enough the plan failed but luckily the seme saved him and did some H-stuff soon after.
Sorry this is as specific as I can get
If anyone knows the story please respond I would very much appreciate it
Thank you! ٩(๑❛ᴗ❛๑)۶