Ranbil, a man who is afraid of love and is studying about love from a book. Including from friends around him, with Thip, a young woman who was once disappointed in love and who was Ranbil's first love, to make Ranbil test his true love lesson.

From college sweethearts to lifelong partners, Pafun and Aioon build a loving, devoted life together—dreaming of a family that seems just out of reach. When Pafun’s longing for motherhood deepens, their hope grows around the promise of adopting a child someday. Everything changes when their best friend, Nubnueng, returns unexpectedly and brings a life-altering opportunity. As love, loss, and responsibility collide, the couple must navigate heartbreak, resilience, and the challenges of becoming new parents. Fulfill is a tender, emotional journey that celebrates chosen family and the power of love to complete what life leaves unfinished.