https://www.pixiv.net/en/artworks/99306821

"The ninja girls are caught trying to skip school to go have fun outside.
In order to reinforce discipline in the class, their master decide to teach them a lesson. That night, he invite the delinquent students into his room, and the girls have untill morning to exhaust him with their sexual skills. If they fail, an even harsher punition await the them...
At first glance, such challenge should a piece of cake for little ninja sluts always hungry for a good fucking. But will they be able to ensnare the man who taught them everything they know with their love-soaked techniques ? Will their pussies squeeze their master's penis to the last drop, or will they mercilessly get creampied until morning ? And what punishment await them if they fail ?"