Obsesion or Obsession: How To spell?
The word Obsesion is misspelled against Obsession, a noun meaning "The act of besieging."
Obsession has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings obse & ion which should not be misspelled with single 'S'
Wrong Spelling:  obse-s-ion  Correct Spelling:  obse-ss-ion 
Find more incorrect spellings of Obsession to spell right way.