Unfortunately played this right as I started to burn out and got a game over. Went up to the Hydra fight and here's what I have to say. Apologies if I'm voting a bit prematurely.
Overall: Lots of potential to really make something amazing out of this core idea, but also lots of room to grow. Would love to see you adapt and improve this for a full-length game.
Gameplay: This is what I was excited for. I've probably made it a little too obvious my passion project is based around a FFXII-style class changing mechanic complete with magical girl transformations, so I'm always excited to see how others approach it. I think this is a very strong foundation and I adore being able to switch classes on a dime to fit the situation. I ended up running a Mage/Gunner/Warrior build and mostly focused on pure damage output. If I needed an emergency full party heal I'd switch to Priestess and use Prayer.
With that said, I think where this game falters is in clarity. Most attacks have joke descriptions and Dresses have none at all. With pretty much no tutorial outside of a single message if you say you haven't played FFX-II, this did leave me a little confused at times. When switching to Dancer, understanding that I'll pretty much only have healing/buffing moves as well as what stat buffs and nerfs come with it would go miles. Some of the battles were also super long too.
Music: Digging the battle theme. RTP remixes are cool but a little on the loud side compared to SFX.
Comedy: The cut-off half-second of Theme6 right before Marsha busts her ass got me, as did some of the attack descriptions.
Graphics: Beefed up RTP works well enough and I love how you differentiated each class's dress. Also a fan of the portrait expressions. Just please consider a different battle transition next time. Took me like half a minute just to transition into each fight.
Story: Has potential so far but dialogue could use some cleaning up.