Sunu makes Lorient loan permanent
"I've just signed a four-year deal with Lorient. My main aim was to join Lorient so that I can play," he said.
"If I get to play up front I hope to score ten goals this season. If I'm on the wing, hopefully I'll score a few goals and help create others."
Sunu, 20, was signed by Arsenal as a 15-year-old but was already loaned out to Lorient last season.
The Frenchman recently played for France at the FIFA U-20 World Cup in Colombia, where he scored two goals.