|Member of The Rose Society|
|Allies||The Rose Society|
The Dagger Society
|Enemies||The Inquisition Axis|
The Dagger Society (former)
Sergio is an elite with the ability to manipulate the weather specifically rain. However, he is only able to start a storm and is unable to control or stop it once it starts falling. When Sergio was with the Dagger Society, they gave him the name of Rainmaker. This name is then used again when he joined the Rose Society.
Not much is known about Sergio before he joined the Daggers, except that he worked on a ship as a rigger. When he was eighteen, Raffaele came to him to convince him to join their side. He immediately refused, but when Raffaele brought him to dinner where he and Enzo demonstrated their powers and brought out a bag full of gold talents his opinion immediately changed. However, his powers did not appear for months and eventually, he caused a terrible drought in Estonia. Desperate to prove his worth, he tried calling upon the rain in the middle of huge markets and in public without any luck. Raffaele demanded Enzo to kill him immediately, fearing he would disrupt their plans. Instead of killing him, Enzo rendered him unconscious using the tip of a poisoned blade, sparing his life and shipped him off somewhere else, leaving only a short note. Sergio has since then held a grudge against the Dagger Society, and is eager to ruin their plans when Adelina suggests so.
Some time after the Daggers abandoned him, he joins the Night King as one of his mercenaries and eventually learns to control his powers. The Night King finds him useful, helping to steal from other ships and conquering pirates that try to steal from the Night King. His group of mercenaries become a part of the Night King's private fleet, and the ship that they yield is called Double Edged Sword.
After Adelina's murder of the Night King, he realizes her powers and offers her his assistance to escape Merroutas. It is when Sergio conjures up a storm to help them get away that Adelina realizes that Sergio was the young boy Raffaele spoke of, the boy who could not control the rain. Sergio and his Mercenaries pledge their alliance to Adelina and the Rose Society with the promise of a fortune, and along the way he grows close with Violetta.
- Rain Manipulation - Sergio has the ability to create powerful storms by gathering individual threads of moisture in the air like mist form the ocean and ice crystals in the sky.
- Swordplay - As a mercenary, Sergio displays an exemplary skill with the sword.
- It is suggested that Sergio has feelings for Violetta Amouteru.
- At the end of The Midnight Star, it is revealed Violetta and Sergio are married.