Just everything. It is cliché enough to train your mind. 
MC should have a mental age of 15–16 but acts like a 6 year-old kid that just breaks a vase when any problems arise.
*The rating might be too strict if the main audience is 12-13 year old though.

... Last updated on March 22nd, 2024, 2:03pm

This has between .5 and 1 point higher an average than it should. Usually these op mc isekai harems are between 5.5 and 6, unless they're really good or really bad. This is, as of now, at a 6.7, even though it's nothing special, and maybe even a notch more shameless in its wish fulfilment than the average offering in its genre. Mc "hides his power" in the most pathetically peek-a-boo way you can imagine. He'll have inner monologue about hiding power, and then go kill a ton of dragons and bring them back to show everyone, and then be surprised when they think he's op. Women can't get over each other fast enough to ask to marry this 10 yr old. He'll put up minor resistance to each one, but ultimately every few chapters he'll get another fiance, but the whole cycle is done in a way that makes women look 1 dimensional characters (as is typical for harems, but is even moreso on display here) and makes the mc look like a doormat that won't stand up for what he wants in the slightest (typical shota, but again, moreso here). It's not a 1 as I rated it, more like a 4 or 5, but I'm giving it a 1 just to try and bring down the inexplicably high average a bit more.

... Last updated on January 19th, 2024, 7:16pm

Could not turn my brain off enough to enjoy this manga, the plot is very base. Might appeal to people who haven't read much isekai.

Very good, love how the author doesn't even remotely try to make MC balanced

This is solid fun.