- Lorenzo Paguro is Luca’s well-meaning, but sometimes distracted dad who’s very passionate about his hobby of raising prize-winning crabs.
In human form, Lorenzo has fair skin, brown eyes and brown hair. He wears a white shirt with jeans, a belt and a blue hat and is barefoot all the time.
In sea monster form, Lorenzo has green scaly skin all around, and has dark green thin fins on his head and upper lip to replicate his hair and mustache. His eyes are still brown, but they have yellow sclera and oval shaped pupils. He also has round, caudal fins on his arms, face, back, ankles and long tail. Lorenzo wears green pants, presumably made of seaweed.
Role in the film
When Luca's mother Daniela takes her son back home, he approaches Lorenzo introducing one of his crabs Pinchy-pessa who is on molting stage, explaining to Luca that the crab he is holding can sense weakness just as his wife tells her son to eat while discussing a plan to beat the Branzino family at the crab show this year.
During a montage of Luca and Alberto privately building a Vespa, Lorenzo feels worried and approaches his wife Daniela upon picking up an alarm clock and a playing card from the human world, explaining to her about the weird objects he found after noticing "Smuca" at the farming area while harvesting seaweed underwater to which they feel confused upon noticing what happened to Luca. Later that night upon returning to the ocean, Luca approaches his mother as well as the objects Lorenzo found to which while discussing with him, he tells him to promise to avoid sneaking off to the surface again. As Luca talks to his parents about his friend Alberto who takes him to the human world, Uncle Ugo overhears the conversation between Luca and his parents about the human world being a bad influence to which Lorenzo introduces Luca to his brother just as Daniela thanks him for coming to her family's home. After noticing Ugo freezing due too much oxygen in the area due to the fact that he has characteristics of an anglerfish, Lorenzo tells his son to hit his heart so that he can breathe to which upon doing so, he explains to Luca's family that in his home that there is no sunlight in the abyssal zone except for the food he finds in his home to which Daniela warns Luca that he will be staying with his uncle for the rest of the season. Instead of staying with Uncle Ugo like what Daniela told her son, Luca risks himself to go back to the human world and manages to go back to the surface with Alberto.
Realizing that Luca went to the human world, Lorenzo and his wife Daniela arrive looking for their son to which the two find themselves in human form on dry land. Reacting to their human forms upon reaching dry land, Daniela then tells her husband to look for Luca and bring him back to his family's home in the underwater world. While exploring the harbor, Daniela tells her husband to stay focused while looking for their son to which upon seeing the townsfolk while not noticing Luca and Alberto passing by. They later pass by a group of children playing soccer across the town to which upon seeing, Daniela decides to "play" with the children much to her not being to used to legs as Lorenzo decides to look for his missing son as Luca hears his mother imitating dolphin noises as the two are having a hard time looking for their son across the town.
During a montage of Luca and Alberto preparing for the Portorosso Cup, Lorenzo and his wife Daniela drop water balloons of some children eating watermelon while looking for their missing son and later when the two pass by a movie poster depicting artwork of a sea monster with the characteristics of an anglerfish, reminding the two of Ugo at the ocean. While Lorenzo plays with a bottle of shampoo for fun, her wife worriedly loses faith in looking for her missing son. After failing to find their son, Daniela and her husband Lorenzo sit by the fountain depicting the statue of a man killing a sea monster with a harpoon to which while losing faith in finding their son, Lorenzo tells his wife that she was trying to keep Luca safe to which the two finally find their son to stop as they are unable to bring him back to the ocean.
During the Portorosso Cup, Lorenzo and his wife Daniela walk past a priest who offers the two a cup of water for each children. Later after getting the water cups, Daniela and her husband Lorenzo offer the cups for the children to which upon seeing Luca, the two attempt to take him back to the ocean but they fail to do so. As the rain arrives at Portorosso, Daniela and her husband shield themselves with a blanket to avoid getting wet by the rain. After the Portorosso Cup, Daniela and her husband barge through the crowd and approach Luca and Alberto who have won the race. Happy to see their son back, Luca happily reunites with them while Signora Marsigliese announces that the winners of this year's Portorosso Cup are Luca, Alberto, and Giulia as everyone celebrates the winners' victory.
During dinner time with Massimo, Lorenzo is served with pasta just as Grandma arrives and talks with her daughter about the good things Luca did. Later the next day, Lorenzo and the rest of his family approach Luca and to which he explains that everything about going to school is all arranged, allowing Luca to stay in Genova with Giulia and her mother.
- Due to Lorenzo's brother Ugo looking similar to an anglerfish, it is unknown if Lorenzo was from the deepest parts of the ocean.
- Despite never going to the surface before, Lorenzo can naturally walk on land while Luca struggled at first. The director hinted that he has probably done the 'change' before.