As for the game, yes, 99.99% chance that it is safe:
- I bought the game on DLsite and I confirm it is the same file that is shared here, so if the game has a virus, it means DLsite has a virus too, which is very unlikely.
- I played the game (and many others here) and nobody has reported anything suspicious since then, except one guy who talks about "something in win32 after downloading the zip" (which makes no sense)
- The game has a weird DRM system which is almost certainly the cause for the antivirus flagging
- Nobody will bother developing a virus for such an unknown game (viruses cost time and money to develop)
In general, don't be unreasonably scared of viruses. I have no antivirus software on my computer at all (not even Windows Defender) and I've literally never been infected. And while I can't guarantee this will never happen, my computer looks much cleaner than an antivirus'ed one currently:
- I don't have constant problems with ports/firewalls blocking games
- I don't have constant problems with false positives / exe being blocked
- I no longer notice random CPU spikes while playing
I'm not saying you should not have an antivirus software, but basically, what you need that is 50x more important than an antivirus software, is common sense.
If you download a popular game on a shady website, and the file is a 2 MB executable that is named "game.exe", then you don't need a software to tell this is a virus.
But if you download an unknown game on F95 which is in zip format, and the guy who uploaded is clearly not a bot, and multiple people say it is safe, then common sense says it is safe, even though your antivirus panics.
Antiviruses are an additional safety, but not one I would consider very helpful, they will rarely be able to tell that something is 100% a virus, often they will emit a warning, and still leave you the decision to run it or not... Because ultimately they can't guess what a program will do, they can only scan the code and see if there are things which increase the chance of it being malicious, things such as installing programs in system directories, starting other programs without asking you or changing their code, using network, etc. Unfortunately, legitimate programs also need to do this sometimes, in this case, the game is probably encrypted on your disk, and it self-decrypts itself when you run it, something that is commonly used to fight against piracy, but scares antiviruses because they see this as a suspicious attempt of a program to hide itself.
Not to mention, if you ever end up downloading a virus, in 99% cases it will just try to put some ads on your browser or mine bitcoin, causing unusually high CPU load in the 2-3 days then you'll quickly notice something is wrong and delete it.