Rakan and Cat Cat's mother are in love with each other. Rakan devise a plan to get the mother, but the mother herself ALSO devised a plan to not use contraception to get pregnant. Rakan himself didn't aware of this.
When the mother's plan succeeded by getting pregnant, she waited for Rakan to buy her because her price had dropped. Instead Rakan didn't came back for her for a long time (because he got blocked by his family by sending him to war for a long time), but mother didn't know about this. Instead, she thought that she got betrayed by Rakan, she had given up everything for him (her status, position, and body) but he didn't get to her.
Basically both the father and mother tried to keikaku without telling the other party and failed miserably.