Obsessions rhymes with:
concessions, processions, recession's, recessions, session's, sessions, sessions', aggressions, concessions, confessions, depressions, digressions, discretions, expressions, freshens, impressions, indiscretions, oppressions, possessions, processions, profession's, professions, recession's, recessions, regressions, repossessions, repressions, session's, sessions, sessions', transgressions
Obsessions sounds like:
obsessing, officemax, opposing, ovshinsky