Carlo Ancelotti has turned down the chance to return to AC Milan, telling the club he needs rest.
Jose Mourinho insists Diego Costa is content at Chelsea in response to reports linking him with a return to Atletico Madrid.
The 22-year-old Spaniard signed for the Blues in 2011, but has been limited to just 22 appearances in that time, and spent last season on loan at Valencia.
Romeu penned a new deal with Chelsea that keeps him at Stamford Bridge until the summer of 2017, however the former Barcelona youngster admitted that should the opportunity arise, a longer spell in Germany would be appealing.
"Maybe I am staying for a longer period of time," Romeu told kicker-Sportmagazin.
"You cannot rule anything out in football.
"I have experienced a technically demanding game in the Spanish league, football in England is more physical, and the Bundesliga is a mixture of that.
"My ambition is to quickly learn the German language."
Despite this, Romeu insisted his focus is to retain a first-team starting berth this season, and make the most of his opportunity.
"I want to help VfB Stuttgart achieve a good season and be a full part of the team," Romeu added.