Traveling Through Another World: I Can Level up by Killing Monsters

[Japanese fantasy] [Monster spawning and upgrading] [Harem] [Adventure] In the year 637 of the Glorious Era, Lin En, who lost his memory, was suddenly thrown into this unknown world. The only one who accompanies him is a system that can help him upgrade, but speaks very venomously. The road ahead is unclear and the goal is unclear, but for him at this moment, just clearing monsters and upgrading is all he needs to do!