You might want to have second thoughts about Seville at that time of year. It will put you in mind of the Mohave Desert. Girona, I cannot advise you on, but Barcelona anywhere up and down the Rambla. Then any side street, also around the Familia Segra Cathedral. Barcelona is to Spain what San Fancisco is to the U.S. If you don't have a good time in Barcelona and can not figure out why, look in the mirror and there is your reason.
Other than that beware of your surroundings,stay safe and enjoy.