Jing is a teenager who starts dating Eiam, a woman who is 20 years older than him. Things go well at the beginning of their relationship because of their optimistic attitude and strong efforts to adjust to each other's lifestyles. However, when Eiam turns 40 and Jing starts to mature, the couple increasingly experiences conflicts and arguments. Things get even more complicated when Jing becomes attracted to a younger woman. 《真爱誓言》的别名有：现在完成进行时,Pra-yok Sanya Rak,Promise Love Sentense,Present Perfect Continuous Tense。