Ah yes. Contra but Touhou. Game is good enough but plagued with gameplay flaws.
-Sticky controls: there were several times where if you press/hold several keys at a time, if you release one, Reisen won't stop doing the held inputs until like three seconds later. I.E. there was a time where I was holding "Aim while not moving" and shooting to the upper-right - when I released "Aim", Reisen not moving until 3 seconds later. Another example: the same but with "Crouch". Another example: was running to the right while holding Shoot. When I pressed Jump, Reisen didn't jump and instead dropped into a pit. I couldn't troubleshoot what causes the controls to stick but really it's annoying when it happens.
-Respawning spots: it's most noticeable in Stage 2. Reisen may respawn on top of a pit, or below a platform's floor hitbox. It's really frustrating and slaps player in face. Combine this with Sticky controls and... well I think you can guess it.
If these flaws are corrected, I can easily see this game being real fun. Look, I've included this game in my showcase video!
https://youtu.be/bFHWSZ1BOBw?t=6034
(Also I legit pogged in real life when I first saw the title screen lol)