It's waaaay less of a harem than Academy Survival Guide. Not sure why it has that tag at all. He does only get travel companions who are women, but I don't remember any of the women flirting with him or the other way around. The women just exist lol. Pure friendship. It's more in the adventure category than Academy Survival Guide is.
In my opinion it's cliche, but well executed. It's a cliche isekai in that he is OP from near the start and just gets stronger as the story continues. However, the enemies are also OP (by the standards of the world he's in), so he still struggles to defeat threats. You get him being awesome and people being impressed with him (the art is really great in action scenes btw) without losing all tension in the fights, as you see happen with a lot of other OP protagonists. He travels through the towns of the isekai world, gets involved in catastrophic events that the residents can't handle on their own, and then he saves them after struggling. He's also unraveling the secrets behind who is causing all these catastrophes while trying to help his companion regain her memories.

Hello hello is this good? I just happened to see the cover and falling in love with that handsome face (≧∀≦)
I see harem tag but is this okay for a girl to read? If it's kinda like Academy Survival Guide then i'm in. Please enlighten me (づ ̄ ³ ̄)づ