Sebastian Hayward

Sebastian Hayward is one of the Hayward brothers that are being attacked by Forsaken Castaways at the Hayward Fishery. The brothers are planning on evacuating by water, but the Shattering damaged their boats and they are in need of repair before they can leave. The Forsaken boats were also damaged, and the survivors have appeared at the Fishery to attack the five brothers.

It's unknown what happens to the brothers after the evacuation.

Relatives
It's possible he might be related to Deathstalker Hayward.