burn

える(もえる) To burn up, intentionally.   $$$
 
萌える(もえる) This is the ‘otaku’ one. Slang meaning, to burn with passion with someone. (adjective form is, ‘ 萌え!’  meaning ‘cute enough to make me burn`. Supposedly the nuance is, the speaker is made to burn, and doesn’t really want to, but is swept away by rapture. Why this is an important distinction for otaku I have no fucking idea.)