Just like Hajime, Franz felt a pang of guilt as she lied to the young miss. He received clear instructions from Mr. Kikuchi that Megumi shouldn't know about their recruitment of Hajime and that's why he had to hide it from her no matter what. In the end, it was his sworn sense of duty as Mr. Kikuchi's employee, and he had to follow that— even if it meant outrightly lying to their daughter.
Webnovel 
Didnt megumi agree with her dad about hiring him as bodyguard back when they were initially attacked? She even said to pay him well
Just like Hajime, Franz felt a pang of guilt as she lied to the young miss. He received clear instructions from Mr. Kikuchi that Megumi shouldn't know about their recruitment of Hajime and that's why he had to hide it from her no matter what. In the end, it was his sworn sense of duty as Mr. Kikuchi's employee, and he had to follow that— even if it meant outrightly lying to their daughter.
A Book Can't Be Judged By The Cover
Realistic · DaisukiDayoSenpai