The midfielder has arrived on a season-long loan from Arsenal with an option to buy.
At today's presentation, Lokonga remarked: "Today is finally the day and I hope to stay for many years because I have a lot to do and a lot to prove.
"I knew that this day was going to come. I have always thought about playing for Sevilla.
"I had some conversations with Víctor (Orta, sporting director). We had the opportunity to talk quite a long time ago actually and today the opportunity finally came true. I knew this day was going to come. Now I have more experience, I am a better player and a better person."
He continued: "Everyone knows that Sevilla has a great history of wanting things. That's why I'm here.
"The most convenient thing for me was the possibility of returning to Europe, winning again and I want to be part of the team, write the history of the team and participate as much as I can."