Fullmetal Alchemist (Original and brotherhood), Gundam Wing, Love Lab, Trinity Blood, Gundam 00, I could go on but there's tons if not thousands of favourites.
Favourite Genres
Action Adventure Comedy Drama Fantasy Ecchi Game Harem Historical Magic Mecha Military Music Mystery Psychological Romance Sci-Fi Shoujo Shounen Slice of Life Supernatural Reverse Harem Space Opera Rom-Com
Favourite Characters
Alot of favourites can't narrow it down so easily.