As I promised, I'd revise the timeline once this was translated. Revised timeline (I thank xenozohar for assisting me with the errors I made with FutaKoi's place in the Dulce Report Series 1 timeline):
In original Dulce Report when Aoi's parents find out there's just a fade to black and we basically get told later that she raped them in to drones, Q's Afterword kind of implies that he wants to draw that now which is both arousing and horrifying.
"How does this take place between two and three, Aoi was way more neurotic there than here? Did something happen that caused her to backslide?"
To quote xenozohar on that:
"And using the events that takes place during the story we can interfere most of the times the story occurs. Futakoi 1 takes place right after the cancellation of the school festival, school festivals in Japan are usually held at the beginning of November (Culture day is November the 3rd). Futakoi 2 takes place during midterms, and semesters in Japan are April-July, September-December and January-March. So it most likely takes place in mid-December, right before the winter break. Futakoi 3 takes place right during Christmas, so end of December, and Futakoi 4 is taking place during valentine day, so mid-February. I really think Futakoi 2-4 are all taking place between Dulce Report 2 and 3 in chronological order, before Aoi turn her parent into worker bees, as I said, this fourth volume shows that the house Aoi is living in during Futakoi 2 is still her parent's."
As you said when FutaKoi 3's translation came out (https://e-hentai.org/g/3146679/6b54368733/), DR Series 1 took place from September of whatever year the series took place to November the following year. The cancellation of the school festival would put DR 2 and FutaKoi 1 in November as Culture Day in Japan is Nov. 3, therefore putting DR 1 in September. FutaKoi 2 would have to take place before FutaKoi 3 as the former is in midterms and the latter being Christmas, which is late December.
@Mr. Ghost I understand the timeline, what's confusing me is Aoi's personality. She seems way more adjusted here than anywhere else in the series, even FutaNanode.