Music streaming company Recochoku surveyed the popularity of anime characters as a marriage partner. The survey was conducted by online questionnaires from May 28th - June 1st. Here are the results:

Female characters
*1, Akiyama Mio (K-ON!)
*2, Katsura Hinagiku (Hayate the Combat Butler!)
*3, Aisaka Taiga (Toradora!)
*4, Kuchiki Rukia (Bleach)
*5, Nagato Yuki (The Melancholy of Haruhi Suzumiya)
*6, Nakano Azusa (K-ON!)
*7, Chrome Dokuro (Katekyo Hitman Reborn!)
*8, Sheryl Nome (Macross Frontier)
*9, Hirasawa, Yui (K-ON!)
10, Soryu Asuka Langley (Neon Genesis Evangelion)

Male characters
*1, Hibari Kyouya (Katekyo Hitman Reborn!)
*2, Sakata Gintoki (Gintama)
*3, Hitsugaya Toshiro (Bleach)
*4, Rokudo Mukuro (Katekyo Hitman Reborn!)
*5, Okita Sougo (Gintama)
*6, Date Masamune (Sengoku BASARA)
*7, Sawada Tsunayoshi (Katekyo Hitman Reborn!)
*8, Kurosaki Ichigo (Bleach)
*9, Sebastian Michaelis (Kuroshitsuji)
10, Hijikata Toshiro (Gintama)

Source: Mainichi