Briska's Things

Looking for a chinese story of 3 high schoolers and their teacher , the first couple is a read head and a white one , the other is of a blondie and the black haired teacher

Both mls are princes , one with red hair , sole heir to the throne since his father didn't want a fight for succession , his mother is a baddie . While the other prince is a captive in the red head's nation , he works as a knight ??? And he has black hair

Can someone enlighten me about the show , and is it only those 7 songs or there are more like actual lenthy episodes , what happened to round 4 ?

Is there any manga or manhwa that embodies the concept of " untill the bitter end " , like mc and antagonist fighting each other dirtly untill the worst ending possible ?

There are a lot of BL with this concept , but what about the other way around ?