Source https://www.pixiv.net/en/artworks/102286041

Nin-nin: But Miko, I'm a ninja too ! I want to train with you !
Miko: Ehhhh don't lie, you just want to stir that useless toothpick of yours inside of us, you perv'. And your small dick is hardly a challenge for a kunoichi anyway, Nin-nin !
Yaku: Don't be like that, Miko. I'm sure Nin-nin just want to be useful during missions - and it could be fun to make him squirm under our bodies...
Miko: You heard that, Nin-nin ? You shall be grateful we are such generous girls !
Yaku: I pretty confident in my fellatio skills, I wonder how long he will last inside my mouth~
Miko: Training is serious ! You won't get away with only 5 or 6 shots, you will have to last till the end of the session !
Nin-nin: If it's for you Miko-sama I can cum as many times as you wish...
Miko: Talking is easy, but fucking between ninjas is hard Nin-nin. It's a serious challenge ! Prepare yourself, Nin-nin, you are going to get squeezed mercilessly by these trained ninja pussies !
Nin-nin: Yay, JK ninja pussies are the best !
Miko: I knew it, you are only being a pervert ! Now come here and let that JK ninja pussy you love so much squeeze you hard till you pass out !
Yaku: Let's empty his balls quickly so that we can go back to our sweet training together, Miko...~

(featuring Nin-nin's brothers, conveniently on a visit from the Shikima dimension that day ^^)