Someone said fish is 19 but idk, doc gotta at least be 25 GreenTea
The fish was introduced as 19 and the doctor is friends with the MCs older brother, whos 20. Since this is a fictional universe, doc could be as low as 22 or so. But we don't know his age, as far as I remember.
im quite concerned about the age gap with the nurse and fish... isnt that literally a teenager