The levity of the situation seemed to drop pretty quickly once Isshin arrived inside Masaki to save her from the giant floating hollow head. I’m pretty sure those two people were a match made in heaven. It wasn’t too surprising seeing Masaki’s enthusiasm at meeting Isshin again, since it was clear that she was worrying about him from before, but it was hilarious seeing her completely disregard the fact that she was butt-naked, for example flashing her boobs inadvertently (or maybe purposely) while asking for his name. She’s definitely not a shy one; ecchi is pretty subdued for the most part in Bleach, and their interactions are great to watch. Sadly, things aren’t great for Ryuuken as he has to break off his relationship with Masaki and leave her in the care of Isshin. However, I do see the potential of him getting together with Katagiri, and maybe she will end up being Ishida’s mother as well.
This concludes much of Ichigo’s background story, as it explains why he is both shinigami and quincy, and also where he got his inner hollow from. After the hollow surfaced in Ichigo, the link between it and Isshin broke, and he received his powers back. Of course there are still other questions to be answered, like whether Ichigo’s sisters also have the hollow inside of them. Unless they aren’t blood-related, I think they should be quincy/shinigami at least, though they haven’t realized the full extent of their abilities yet. Finally, there’s the big mystery of how Masaki actually died. Isshin makes it clear that the whole story with Grand Fisher was not true, but what actually happens is still up in the air. It could be Aizen, one of the quincies/shinigami, hollow Ichigo, or anybody else really, but this is likely to have big implications. Regardless of what it was though, based off what we know of their relationship from the very early chapters of Bleach to the current flashback, Isshin must have been no less than devastated when their family lost her.