Don't worry, Kloff pays in the third timeline. He ends up miserable, drowning in guilt because he realises that he'll never be able to have the Aeroc he abused and that he will never be able to make it up for him. He'll recognise that it's over, the og Aeroc is forever dead and nothing can change it. The third timeline Aeroc will never be able to fill the gap in his heart.
That's what happens in the novel.

This is just so unfair. Aeroc has his retribution Meanwhile Kloff who has done much worse can have an undeserved happy ending in the 3rd timeline. If Kloff at least can understand and acknowledge his evil doing in the 1st timeline, at least there's a little contentment. Unfortunately, no. Kloff still believe what he did in the 1st timeline was justified. Despite finding out the reason why Aeroc acted and behave what he did, he still blamed Aeroc for it. Just a selfish disgusting character through and through