Sengoku no Imouto Shichinin no Imouto

Setting is old Japan.

Your village asked you to go and hire bodyguards to protect it against the bandits, so you went with your younger-sister-like-childhood-friend Suzu-chan and hired six (technically five) people, all girls. When you came back, the villagers become suspicious of those people they didn't know, even more since they were all females and they couldn't imagine them being bodyguards at all.

In the end, you lied and persuaded the villagers that the girls were in fact... your sisters, whom your father left everywhere... (your father had such a reputation...)