I was actually quite mad that he whip him while reading it the first time. How can you do something like that to another person? but as I read further, I was reminded that Sasha was also cruel to Aya. Years of abuse and bullying, no wonder he couldn't think straight for a moment (Still not saying that its okay to whip someone) but violence always led to more drama.
However, Aya regretting this mistake after it happen is sad but real. After all, we're only just human. We all make mistakes (big and small) and the fact that he regretted what he has done and learn from it was great.
From his actions afterwards, you could tell that he really regretted what he has done and that deep down he really loves Sasha.
It was a beautiful story and both character still have so much more potential to grow. Especially Sasha who was an arrogant, prideful, spoil little prince.
Vol.4 ch.2 made me cry especially the whipping part ┗( T﹏T )┛