Simplify the following text for a Grade 13 native English-speaking person.
Original: The anime version of the series aired in Japan from April 7 , 2007 to June 30 , 2007 , containing a total of thirteen episodes and two additional episodes currently being released exclusively for the DVD .
Simplified: An anime version aired in Japan between April and June 2007 ; the anime contained thirteen episodes , and two additional DVD-exclusive episodes followed .