One of the old Western manga publishers, I can't remember which (was it TokyoPop?) use to provide a glossary of terms at the 'back' of the volume, which if reading left-to-right in Western fashion would be the front. So, if you're unfamiliar with manga, that's where you'd naturally open the...
Stated by the author, though Stellaris is obviously also playing a role. As of the current material in the webnovel, I'm also wondering if Sword of the Stars is making an appearance too.
I'd say it's more he's only just started to climb out of his mental issues, and certainly hasn't gotten to a particularly healthy place yet. Plus, Rifreya is from a prominent family and he doesn't even have a history in this world, so couldn't explain his presence, and her family as Temple...
That'd be a weird place to end. From the looks of the thumbnails:
I think it would have been better to round things off here rather than go only that much further.
If there are only six chapters left until the manga finishes, that's quite strange. The novel goes quite a bit further and has several more arcs.
There's quite a lot left to go, building off the character development Hikaru has made to this point.
The author said he only wrote the first half-or-so of the story he could imagine, but it was an experiment in his writing in the first place so it's not exactly like saying he only wrote half the planned story. He rounds it off well, with satisfying conclusions to the problems the story started...
It ended at an acceptable point, but the author did say it was only about half of the story and a lot of threads were left hanging. I live in hope it gets picked up some time, I consider this one of the better WNs I've read.
Sorry, is this arc really saying "Hey, you have amnesia due to brain damage from significant trauma, how dare you you unforgivable bastard."
Isn't there any sort of limit as to how much someone can be blamed for things outside their control?