Okay, kiddo, so a showmance is when two people who are on a TV show or a movie set start to really like each other, more than just friends. They might even start to behave like they are dating, but sometimes it's just for the show or the cameras.
It's kind of like when two people in your class start to hang out a lot and do things together like holding hands or giving each other little kisses, but it's not always real or serious. It's just something they might do for fun or because they really enjoy each other's company.
Sometimes people enjoy watching showmances because they like to see two people who have great chemistry and seem so happy together, but sometimes showmances can get messy because feelings can get hurt if they aren't real or if one person thinks it's more serious than the other.
Overall, showmances are just something that can happen when two people work together on a TV show or movie set, and it can be fun to watch, but it's important to remember that they might not always be real or last very long.