The Uruguay international midfielder joined the Tigers from Southampton late on Monday on a season-long loan deal.
The 23-year-old moved to the Saints from Italian club Bologna in August 2012 but lost his place in the starting line-up last season and started just three league matches while also struggling with injuries.
Having failed to impress new Saints manager Ronald Koeman at the start of the 2014/15 campaign, the former Penarol attacking midfielder has been allowed to go on loan to the KC Stadium.
Ramirez has now stated that he did not hesitate when he heard of Hull's interest and is keen on doing his best for the Premier League club.
"I'm so happy to be here and I'm eager to get started," he told the Tigers' official website.
"I want to show the Hull City fans what I can do. It was a quick decision to sign here once I knew the club were interested. Many people have told me about this area and what a lovely place it is. Also, I know this team is like a family.
"It can sometimes be difficult to have change in your life, but I believe this will be a good season for Hull City and for me. There are many fantastic players here and the manager made some brilliant signings this summer.
"We must all come together now to get results on the pitch and do our best for the fans. It is all about results. We must work hard during the week to be stronger on matchday."