Daily Life at Hogwarts

When Albert, an ordinary unambitious man, is reincarnated into the past with a system, he thought he could lead an easy laid back life. That was until he suddenly got invitation to attend Hogwarts by an owl. Realising that he was in the Harry Potter universe, as a muggleborn wizard before Voldemorts return he needs to prepare to survive what's coming. But Albert hasn't given up his dream of leading an easy laid back life.

Becoming fast friends with the Weasly twins and Lee Jordan he has a two year head start before Harry attends Hogwarts and Voldemort starts plotting his return. Along the way he stumbles into unexpected inheritances, while finding a partner for this life. But as he grows in power and renown, he enters the Death Eaters and Voldemorts radar and has to ensure his own and his family safety.

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Original Author: Lazy cat on the keyboard, translation by me.

No Harem, the romance is slow (they're all kids at the start of this after all...), but it's one of the major subplots of the story, him finding a partner and marrying her.

Light on the LitRPG elements, but they're there. It's mostly MC getting quests, giving him skill points upon completion, which he can then use to boost his skills, but every spell is it's own skill, so he doesn't suddenly get OP, but still needs to practice a lot, most of the time you will simply forget he has a system.

MC is older than Harry by two years, he attends Hogwarts with Fred&George. He doesn't insert himself into the main trio and mostly keeps out of the plot, only doing what he needs to get some good quest rewards. If this FF was told from Harry's perspective Albert would be more of an important supporting character, more akin to the professors and not really a friend of Harry's.

MC has extensive knowledge of the plot and makes use of it.