A Kiihakai Darkness (Adept) MC gets quite a bit with the ritual and the suckerpunch against Kagura (with soulstealing and Techniques like that).Guiren quest should be unlocked as long as you do the Tavern quest in chapter 6. So you can get it as honourable MC too.
Honestly the worst reward is probably for Leona quest rn.
- She blocks the gambling till you either do the heist or reject her.
- Only Kiihakai get like extra 30 AP from that quest. So for others that's a miss.
- The swords you can get don't really feel worth it to me. Just make your own if you have 4/5 lore.
The betrayal at the end is the worst though. I am not offended about the fact that she tried to rob us, I am offended about the fact that she betrayed us over a bunch of trash swords. So disappointing that you can't just beat everyone there up then just leave the swords there anyways because they are beneath us.
Or atleast show her your own weapon if you get all 4 enchantments.
So far, as always, only kuro gets the good stuff from their style with that dual wielding technique, meanwhile Kii users just get silver. Hopefully Scrying will unlock some good stuff though.
Aside from that, Leona has the romance event with giving her both the swords, so it has it usages.
But it does feel as the one you get less when compared with Guiren and Desdemona.

