Anime production studio Ixtl has announced on their official website that they fired illustrator Miyata So, the art author of Muv-Luv Alternative: Total Eclipse novel. Miyata is one of the key illustrators of adult game developer age and the original character designer of Total Eclipse series. There has been a suspicion of plagiarism in Miyaha's official illustration published on Animage magazine July issue.

Comparison between Miyata's illustration in question and the plagiarized ones
Comparison between Total Eclipse official hug pillow with Miyata's illustration and another hug pillow of Shinkyoku Soukai Polyphonica

The contours of the characters in Miyata's illustration seem to be copied from other works of Ikkitousen, IS: Infinite Stratos and To LOVE-Ru.

Source: Announcement by Ixtl (PDF file)