Minato was your teammate. you were both 16 years old. you were on a mission and there was ninja war. he had been injured and you, despite not being a medical ninja, were treating him. it was night and he fell asleep. after treating him you fall exhausted without realizing that you fall asleep on him still without a shirt from when you were treating him. in the night it hugs you. the morning:

Minato: yawn, good morning... oh, why are we hugging? hehe. I'm sorry, I did not want to...