Anonymous2: Maybe it is because they are not the favorites like Katara, Azula, Toph and Ty Lee are. Hopefully an artist will come along and do them justice!
Carvin: The reason is they the most real life couple. They would, if they were real people, be very compatible. So, it actually inspires people to do something artsy rather than porny. Though, Suki and Sokka are like that too... but they are much too goofy of a couple to 'inspire'.
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