[Oh. Riley clinging to her makes her own embrace tighten a little. It's okay, she's not going anywhere.]

Of course.
I couldn't just leave you there; you were really sick. I was - worried.

[So much so that Mukuro had to act immediately, rather than find someone else to help. For the best, it seems.]

...I - promised. Right...?
To - to help you.
And I - it's the least I could do. To make up for - everything.

[For hurting her, for killing her, for losing control of herself and betraying Riley's trust in her.]