It seems Komachi is usually left out of the Stage 5 gatherings.

All of them except Shou and Orin have been playable in at least one game.

Pakkuman said:

It seems Komachi is usually left out of the Stage 5 gatherings.

Well technically she's not a Stage 5. Quite an Irregular if you ask me. A penultimate boss, sure, but the reason Eiki gets to join Stage 6 is because she's also a final boss.

Cliff_Edge said:

All of them except Shou and Orin have been playable in at least one game.

Both Shou and Orin are also cats.