The Blue Whisper aka Yu Jiao Ji (驭鲛记 –> 与君初相识) is adapted from the novel by Jiu Lu Fei Xiang. The drama follows after our hero – the unlucky merman, saved a princess and is then captured to be her pet. She wants to tame the merman and it is said that only those who are born with the power to tame demonic creatures can manage that and they are called demon masters (sorry not technical here). Demon masters are forced to live separately from their families per the imperial decree (to control and enslave them) and they are only allowed to live in four designated areas (north/south/east/west). The Princess’ eunuch transports the merman to the most renowned demon master in the south, where our heroine is currently residing and training. The princess wants the demon master to do three things in 3 months. 1) Make the merman speak 2) Turn his tail into legs 3) Make him eternally loyal to her.
And as such, the merman is subjected to daily torture and punishments for not doing what the demon masters want. At night, our heroine would sneak into his prison cell and tend to his wounds (T_T) There’s a scene where our heroine doesn’t want to force the merman to do things against his will and so she’s tortured (whipped) per the Princess’ order! Our heroine’s backstory is quite sad. On the outside, she’s the most beloved student of the Current Demon Master of the South, but demon valley has been nothing but a prison for her since she was sent there to train at a very young age under some not-so-pleasant “monthly” treatment that she can’t reveal to the outside world. Which is why she feels empathy for the imprisoned merman and wishes to help him escape, landing her into a lot of bloody messes.
You can read the translated novel here @ Way East.