Thank you so much for buying and playing the game! I'm very happy that you enjoyed it that much. :) If you've completed everything you should have all gallery images, did you do the DLC as well (which you can choose to start when starting a new game)?
There's an achievement guide on the wiki (bottom of this page) in case you want to go for full completion: https://purgatoryverse.fandom.com/wiki/Pitstop_in_Purgatory
Thank you again for the support, for playing and for leaving this lovely comment! <3