As an adjective happy
is experiencing the effect of favourable fortune; having the feeling arising from the consciousness of well-being or of enjoyment; enjoying good of any kind, as peace, tranquillity, comfort; contented; joyous.
As a noun fanny is
(british|irish|australia|nz|south african|vulgar) the female genitalia or
fanny can be (uk|naval slang) mess kettle or cooking pot.