Played this for a while and figured I'd give my feedback now despite not having seen all the content since I'm starting to get distracted by other things and I'm not sure when I'll continue playing.
If there's anything you could do to make each action or turn take even a bit less time it'd be great, the game is kind of grindy which isn't necessarily bad but definitely amplifies how annoying things being a bit slower than they need to be feels.
I haven't actually worked with Ren'Py and know nothing about how you've set things up so this is just a random idea that might help with the problem I mentioned, if you are deleting and recreating the enemy sprites between battles, you could try doing that only when changing area so that once you're in an area the start of each battle doesn't need to take as long(or if there's another reason for why starting a battle takes so long I'd be glad if you addressed whatever that reason is).
Some way to disable, skip or speed up most battle animations would be nice, having paid attention it seems like you've done that to some extent(most spell animations seem to get cut off if you click during them) but it took me being about to suggest you add something like that for me to notice that so more could be done to communicate it and make it feel better. Making the animation finish and/or the next line appear as soon as I click would make things feel more responsive. Potentially decent option that I thought of would be to have the turn animations play in order independently of the line you are on so that you don't need to interrupt reading or deciding what action to do next just to wait for the animation to be done(if getting a message just about casting a spell while the enemy's attack animation's playing feels weird you could try having one message for all actions in the turn). But who knows what'd be best, a disable animations toggle in the options or such might be better in the end.
Needing to move the mouse across the screen depending on if you want to cast a spell or do something else isn't ideal, keyboard shortcuts for at least the left side buttons would be nice.
Anyway, for the actual story content I really like what the game is going for and there were several situation that got me to excitedly imagine what'd happen only to be sort of disappointed and think oh, well maybe later. Here are the notes I wrote about most of them:
- Lucan dragging me off was kind of sus, I was expecting it to be a trap or at least have some nefarious purpose behind it.
- Magical Toy Wonderland's first quest was kind of disappointing, with how evasive the guy was being initially I was expecting it to be lewder than it ended up being(I expected magical toys to include some sort of lewdness either in their use or making them instead of them just being able to talk(I suppose them talking in a more perverted/suggestive way instead of just cursing would have satisfied my expectations slightly)). Being (temporarily) turned into talking toy would be hot and would kind of explain the way the the balloon was talking, I suppose something like that could be a later quest. For convincing a fairy I was expecting to have to either please the fairy or maybe entertain one by doing something lewd. Getting a berry for the fairy also had potential for something interesting though not overtly so(having a choice between a normal berry and something different with some sort of special effect could have been neat and I suppose instead of eating she could have wanted to do something else with a berry, also image of a fairy with a stuffed stomach could have been nice)
- Morden wanting me to come to his lab made me wish for something interesting to happen. Being told to carry around a demonic stone with unknown runes was interesting until he said that he just wants me to ask around for translations but he could have just given a paper that has copy of the runes so there's still a chance that it's just an excuse to get me to hold on to it and show it to people which could potentially have interesting consequences(ie. the stone could be meant for forming some sort of contract for slavery, marriage or such or it could have some sort of effect on the carrier)
- Magical Toy Wonderland's shoe quest made me think of lots of interesting ways things could go, ending up body swapping into the "wife" and being under the influence of it's programming to some extent(could be simply as having the skills and know how without any requirements for behaviour or as conditional compulsion to act out programmed behaviour) would be nice and while continuing to play as it while potentially leaving your original body for Nel could be nice it might be too much work so just having some way to get back to your body and either leaving the doll dysfunctional or getting the assistant to take your place(as a way to pay his debt or sort of escape it or just because) might be easier way to make it more enjoyable for at least me.
- Both when Nel was first done and when the slimegirl was done I expected them to not actually have left and just somehow still be with Celia. If there isn't already, might be nice to have some similar situation like that where she's wrong about having been left alone and free. Maybe with some other character since for slimegirl just not leaving and staying around in an obvious way would be more reasonable than her somehow hiding inside your ass/pussy or such and for Nel there are various events of Nel being around unexpectedly that already kind of do similar things but not sure what exactly I'd even want to happen now that I've thought about it more, I guess some sort of, "Hah, you thought I was gone but I'm still around and in control, I just decided to leave you be for a bit." situation.
- Library mentioning a lack of gameover scenes or such was actually kind of disappointing, is that an intentional choice of not wanting to reward losing/playing badly or just due to not having had the time or motivation to make such scenes? If it's the former there are some ways to do the scenes that'd typically be gameover scene without actually requiring you to lose a battle, something like just entering a monster nest willingly could work. Also something similar to the battles that you do need to lose could be nice, it's kind of weird to be able to just wait forever while monsters play with you without anything really changing so something like after two to four orgasms the enemies win and you get a scene of them having their way with you until they are satisfied.
- I really liked the scene where you get the dildo from Nel and the scene where you try using it on your own, made me look forward to/hope for when you end up getting in the habit of asking/letting Nel to use it for you.
As for graphics I really like the style that the map's town graphics are made in. Wondering why I specified town made me realize that while nice on their own the trees are perhaps a bit too busy and detailed and aren't as pleasing to look at as other things(trees during battles do look nice).
Overall the game is nice and made me more interested in possession content than I was before so that's great.