The Japanese language is syllabic - instead of single letters, Japanese is built from entire syllables consonants (except 'n') don't occur by themselves. Portmanteau words are the Japanese equivalent of acronyms. Sometimes, the producers explicitly encourage this, and refer to the series using the nickname in the Post-Episode Trailer. Frequently, they wind up picking up a portmanteau series nickname, with a syllable or two of each word in the series name. Many anime, manga, and especially light novel series have fairly lengthy titles.