ᴍʏ ʟɪᴛᴛʟᴇ ᴅᴀʀʟɪɴɢ (ʙᴀʙʏ ꜱᴀɴᴢᴜ)

Sanzu were stupid enough to drink a random chemical or chemical (whatever) out of your work table
Yet had made him into a baby. The drug only works for a week, y/n needed to wait for sanzu to come back to normal.

Now now~ let's get into the story