Heck if I know, though I do know that games made in Clickteam Fusion 2.5 seem to like to be picked up as false positives through heuristic analysis. I'll run it in VirusTotal to see what other scanners might also be complaining, and then see what I can do to get it all cleared up.
...I've run it through VirusTotal and VirusTotal doesn't seem to pick it up as being scanned by Windows Defender (a select few other scanners do pick it up though apparently)? Weird. Well uh, feel free to submit a false positive report here if you want, or you can tell me what definition version of the program is causing it to be picked up and I can do it myself (the definition version isn't required but will make it faster): https://www.microsoft.com/en-us/wdsi/filesubmission
(Here's how you can find out what definition version you have: https://docs.microsoft.com/en-us/windows/security/threat-protection/windows-defe... )
For what it's worth, the Five Nights at Freddy's games also have issues with being detected as false positives, and were made in the same engine. As with many other Fusion-made games. It's always a few random scanners, McAfee appears to be a particularly bad offender there though.
That being said, I have no idea what the heck happened here and if you want to remove it just to be on the safe side, I can't blame you.