Sebastian is the main antagonist of Best Friends Whenever's second season. He wants to force marriage on Princess Daisy in 1522. He is the second villain to appear, first being Janet Smythe. He is portrayed by Barrett Carnahan.
Sebastian is a young arrogant Nobleman from 1522. Although they have never met, he and Daisy have been betrothed for two years. When Shelby and Cyd inform him that Daisy wishes to break their engagement, he will not release her from their arranged marriage easily. He is egotistical and vain, and is a bully towards others. He is also misogynist
Sebastian appeared in three episodes of Best Friends Whenever,
It's Not Me, It's Ye
Revenge of the Past - Parts 1 and 2
He and Daisy had been betrothed for two years. In It's Not Ye, It's Me, he lost Daisy in a battle "to the death" with Shelby and Cyd (fortunately, Cyd spared his life).
Cyd and Shelby
When he had first met them in Daisy's time he was arm wrestling Cyd and later he and Shelby (dressed as a man) were fighting to the death until Cyd intervened and successfully defeated Sebastian while Shelby knocked him out.