http://www.dlsite.com/maniax/work/=/product_id/RJ234228.html
https://www.dmm.co.jp/dc/doujin/-/detail/=/cid=d_136110/

Originally released 2018-09-28, updated 2018-10-18.

002-156: Text
157-311: No Text
312-380: Update (Text)
381-449: Update (No Text)

I swear I have seen this before
Oh right game cg by ichikawa noa
https://e-hentai.org/g/1105805/b0a98f7702/
is this somehow related in any way ?

Base +23, KitchFatimah +7, darkwarlord +8, as102 +10, Megaton +39, Smashproof +9, pauldown321 +1

I had no idea, what a lame thing for a circle to do. Just use someone's art and then add text over it. Dang.

Base +56, darkwarlord +8, as102 +10, your_name +6

I assume this was done with permission from the original company. This isn't the first game to have been repackaged as a CG collection (for example: https://e-hentai.org/g/1175214/b19e47118d/).

The following message is at the bottom of the product page on DMM:

本作は版権元の許可を得たコンテンツです。
"This product uses contents with permission from the original author."

That message is a little vague, actually -- TGA has slapped this exact message on all of their product pages. Compare that with RemationMade (https://www.dmm.co.jp/dc/doujin/-/detail/=/cid=d_119330/), which clearly states the license holder and the base product name on all of their titles. Hmm.

Base +12, as102 +10, Megaton +39, Manonymous Rex +5, m674456 -6

I think there is an animation based on this.
My bad it was a different game with the same artist. No wonder the character designs look similar.

Base +6, XerxesDraconis +9