mysterious stranger

Lily and James Potter were having a fight do to Severus Snape-Prince, Lily's childhood best friend. She wanted to reconnect with him, but James was against it, becauce Snape had insulted her as a moodblood and had jet to apologize. In the heat of the moment James let slip that he discovered that he is infertile. Lily stops arguing and is heartbroken, du to really wanting to have kids.

L: "Did you just say that you're infertile???"

J: "..., yes sorry that I didn't tell you sooner. ..."

L: "... okey ... let me... let me leave for a bit. ... I haveto digest this."

Lily left the Potter Manor and went to a bar in the Muggle London to drown herself in her sorrow. She drank cup after cup, do to her being to drunk to realize what was happening, she ended in a hotel in bed with a stranger.

Who is the mysterious stranger?

Will they make up again?