Idk to me it just felt like the reintroduction of both mom and Jaeon as in they are both back for Yeonwu and Rosa and fun is over...
Jaeon said nothing hits for him anymore indicating that Rosa ended up meaning way more to him than he thought so I believe he will have a comeback to get her back and as for the mom it's obvious she will go back to Yeonwu and there is also the wedding...

Mommy's back.... Is that subtle foreshadowing that hes gonna start getting freaky with the mom? Toy switching between mom and daughter?