Kael_9903

I think it's almost the same as the Servant case and also if Mc tries to steel Life force Servant Artoria, Servant Artoria will immediately become a Heroic Spirit at full power to kill Mc because she is still under the Alaya/Counter-Force Contract to eradicate all potential that endangers humanity (Kurumi/ MC power which basically eats 'Time' to use his power will be hated by the Counter-Force because of its potential to eat humanity slowly but surely)

that won't happen because the servants summoned during the Holy Grail War are not full Heroic Spirits but copies of the Throne of Heroes. MC can eat servants but will not get limitless Lifeforce from them, at most only above the average of the humans he usually eats.

My suggestion is just to have a story first before harem because many stories never progress since they are still stuck/too focused on the harem story rather than the story itself.

The Nekomata massacre never happen in story but it was a fan-canon/fandom from a fanfic "a Demon lord hero by Fahad09"

man, when Subaru and his mother relationship started to improve, Subaru ended up in isekai, and so the Soulborne Playthrough began, where he died frequently.

maybe the barrier will soon be destroyed trying to withstand the attack above high-high class

You have to remember the MC has only been exposed to the supernatural side for a few days so he was introduced to the first rule of the supernatural, “only those who become monsters/strongest can survive in that world”.

I mean, have you ever felt like killing someone and felt bad doing it? What I mean is that I hope the MC doesn't become Murderhobo and feel like every moment he has the power to take someone's life and feel normal because his enemies are weak or have morals that are self-righteous.

I hope MC will only considering killing as a last resort for self defense