Vol 11 is split into 2 parts

Chapter 1 and 2 happens right after vol 10 when they came back from Erloid

The quad stayed in capital city for quite a long time and darkness suggested going back as not to cause too much trouble

Kazuma resisted but eventually can't argue with her, told the girls to head back first and he can say goodbye to Iris

Iris made moves upon Kazuma

Kazuma be like "nooo I'm not a lolicon"

Iris used "onii-chan daisuki", super effective

Kazuma stayed in capital but starting to have bad influence on Iris(teaching her rude words) and eventually Clair forced him to leave, also forced him to take memory-erasing pills

Kazuma struggled and suffer quite a lot in this part

Somehow it is reveled to Clair that Kazuma is the leader of the infamous thief group in the chaos. Kazuma threatens to use steal on Clair making her cry and run away.

The reason behind illustration where Kazuma and aqua is having a fighting is Aqua being upset because Kazuma decided to stay at capital.

The arc ends with Aqua used too much heal that also canceled the effect of memory-erasing pills and Kazuma keels down to apologize.

Komekko's part

Demon king's daughter is leading an attack on crimson demons clan leaving komekko homeless. She was brought to Axel by Dondonko and funifula while most of the crimson demon clan were driving off the demon king's army.

The guild used Komekko's innocence and kawaii-ness to get adventurers to clear quests no one willing to take.

Kazuma was given the most notorious quest to deal with Tranquility Princess, a badass version of tranquility girl from vol5

Kazuma dispatched her (basically Kazuma(f) vs Kazuma(m))

Megumin didn't get to show her power and komekko thought she isn't strong enough

So finally the quad took the quest of killing griffin and manticore mentioned in vol2. As usual Megumin took both out with explosion.

Two things happens in epilogue

- Megumin wanted to take the relationship between she and Kazuma to "above friendship below lover"