Elf's rhymes with:
delfs, self's, selfs, adolf's, delfs, gandalf's, golf's, golfs, gulf's, gulfs, ralph's, ralphs, rohlfs, rolfes, rolfs, seawolf's, self's, selfs, wolf's, wolfe's
Elf's sounds like:
el-paso, elapse, elbows, elfish, ellipse, elopes, elves, elvis, elvis', elvis's