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I'll keep it a secret, so let me spoil you ~ The curt younger minister is only hard on me

Chisato is a very talented girl who works in the General Affairs Department. However, her only concern is a junior mid-career employee who has recently arrived at the company, Yoomin-kun.
They used to play together when they were little and now they work at the same company, but now they are just colleagues.
Yōomi has no trace of the cute face he once had, and his attitude is curt. The relationship is more convenient now that they are not childhood friends.
But at his welcome party, he leaked something about my past to me...?
Chisato takes Yotomi out to shut him up, but when he whispers "Chi-chan" to her, she can't stop her heart from pounding!
Furthermore, Yoomi laughs like the spoiled child he used to be when he hugs her and says, "I'll keep it a secret from everyone, so let me spoil you."
After a chance reunion, his feelings for his beloved older sister continue unabated.

U rarely see shojo art-style used for hentai works. Not bad.

Base +6, Fofotron +9