Seems like one of those cases in Japanese when a single word can mean from "older person" to "father-in-law", TL chose the latter term to convey this possible meaning, but it sounds really weird in English without knowing the context I think @Kurogwane nailed it above.
Unfortunately, the translation you guys chose kind of makes no sense in the context, not to mention that it doesn't even have a punchline, just a (quite obscure) reference. A direct translation would make far more sense.
Anyway, you're doing a great job overall, a meme translation or two is more...
Exactly. I can even imagine the title:
"I am an unremarkable loner, but whenever I act like a recluse all the totally existent-in-Japan busty blonde mixed-heritage goddesses cream themselves over~~~? My journey to a room on future with a cheat skil-, I mean, just being a Japanese nerd~~~!"
Nah, he cares more about people he doesn't even know than his brother. I hate him and I hope he gets the worst pairing possible, which atm is stalker-chan.
Childhood friend? What did she do to deserve this shithead?