Yes. If you don’t mind spoilers, this is how the novel ended for Cliff:
Yes, he did marry Rise. They actually did inherit the dukedom from the parents and Edith and Killeon inherited a small territory and became Count and Countess (they actually like this set up since they can build their own territory from scratch the way they want to. Both of them work very hard for that territory. Killeon even jokes that Edith seems to love the territory more than him as she’s such a workaholic. Haha) However, Rise was incompetent as a duchess to say the least. She always wanted to be adorned with countless jewels and she wanted to somehow prove that she’s better than Edith. She set up a plan to find the missing prince or something but ended up not finding him and instead presenting a fake child. She was charged for this crime and was stripped off her title. Cliff and the parents slowly realized Rise’s true colors during this time and were deeply disappointed by her. Cliff and her eventually divorced because of the fake prince scandal and she was sent to the nunnery.
Cliff was understandably very depressed after that. I mean, he did really love Rise. He wanted to quit being a Duke as he believed that Killeon would be much better suited for the role since he utterly failed as a husband and as a duke. But Killeon and Edith dissuaded him from doing so (plus they didnt want to give the territory they already adored). After some time, Cliff eventually remarried a calm woman and had kids with her. The romance might not have been fiery like with Rise but she was the woman who eventually gave Cliff what he actually need, a peaceful life and a loving family (yes, they had kids). His new wife, from what I gathered, is very nice and amiable. Nothing much was said about their love story besides that.

Is it just me? or do I think Cliff should give a second chance? I mean he's just wants love. He is just also controlled like in the story. They made him obsessed and possessive on rhyse. That's why when she's no longer the rhyse he knows he was like going crazy that he also fallow the her, the author. He believes she was his only lights. He was influenced please don't judge me it just base on my opinion.