Late night || Kokonoi x reader x Sanzu || Smut

Y/N usually goes to the same library every day to cool off her mind, but one day in particularly she met two of her old childhood friends,...
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I wanna say that the characters aren't mine, so credits to Ken Wakui
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This is happening while koko and sanzu are in bonten so all the characters are over the age of 20, including Y/N
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All the pictures you see here don't belong to me