Disgaea 2: Dark Hero Days

[LunaMoo]

@The_FunkyDealer make sure you don't use "Disable Alpha Test" hack, as having it on will give this in Disgaea and cause lots of similar glitches in other games.

As a rule, you should avoid using hacks unless you absolutely need them for something and when you do, you have to accept that whatever improvement they can bring by design they will cause other issues.

As you can see, game should work normally without hacks in latest versions:
   
so if you don't use this hack, you should try latest ppsspp version from buildbot and if it doesn't help, post more info about your device, alpha test should not be a problem on pc's and you seem to run on windows so it would be weird.