You describe the case of the game to him and ask him to get it for you.
"Wait that's what that was? I saw some rats down here carry it away before I even came up here, it's long gone by now"
You let out a sigh not at the fact that he could have stopped the rats earlier but more so due to the fact you wasted some money today, feeling defeated you turn around to leave John alone and go to your favourite bar since you need a drink after the events of today.
Before you leave though you hear John shout "Wait! Mortal where are you going?"
You explain your going for a couple drinks and before you know it John has fully climbed out of the Storm drain and is willing to come with you to get some drinks.
You spend the rest of the day and most of the night drinking and having fun with your new friend The Master of the Storm Drains John.
(Damn this is actually a good ending for this branch isn't it? A bit rushed though but it's got me tearing up I hope you and John have a good life, yous seem like you could be really good friends if you know each other more, also it's up to you if you think this is canon, Hell if yous want I might make a branch one day with a UserXJohn Ship I could see some romance there couldn't you?)