Ok, so I began consuming lewd games around 2015/16. For a while I just kept the ones I liked. Then I installed a dedicated SSD (2TB) to the task and started a spreadsheet. Then I started changing the file names to reflect my opinion on the game, because I couldn't recall what I liked and what I hadn't look into yet and the spreadsheet was to much work. Then that got to convoluted and I had to many unviewed games clogging my drive. so I started keeping bookmarks to promising titles. Then that got WAY to convoluted. So I revived the spreadsheet and completely overhauled it.
If a title looks promising from the synopsis and images, I record it into the sheet.
The spreadsheet, currently is: (Formula to see if i've repeated a title), Game name, Developer, Status (complete/incomplete/abandoned/etc), My overall score on a personal scale (0=unviewed, 1=hated it, 2=disliked it, or was so loli heavy I was uncomfortable with it, 3=neutral opinion, it's average, 4=I liked it, 5=I liked it a lot, 6=I loved it, and likely gave the developer money), How Likely I am to revisit this game (fap material, future updates, whatever), graphics quality, story quality, humor quality, depravity (as aligned with my tastes), enjoyment of playability (mechanics), what software it was built on, comments to myself to remind myself of notable features or whatever, Link to Fuck95 site for the game, Link to LC site for the game, Link to one of the other sites (I seldom look at any others, so I don't have a dedicated column for those).
So, what I do, when someone makes a request, and I have time to do this. Is I go through the list (in alphabetical order) and glance at the titles that have a rating above 0, meaning I have at least played them. I do a little mental check to see if I recall the game meeting those criteria. If I miss one, oh well... If it does meet the criteria I record it, leave a blurb about why it triggered my memory and move on.
At this second there are 1362 lines in the spreadsheet. Also about 100 tabs open to be looked at. It takes about 20 seconds to add a line, because until I play it I'm only recording seven items (Name, developer, status, graphics, software, comment, link).