"suteki no t-shatsu desu ne!"
(that shirt is stylish you know)
Suteki is japanese for "beautiful". Like some other Japanese words, fans of Japanese culture will sometimes use this word in their english sentences.
A distinction must be made between "Suteki" and "Kawaii".
"Kawaii" is cute, a less serious word.
"Suteki" is beautiful, a word with more impact and used in more serious context.
Kawaii would apply to a plush toy, a figurine, or a costume.
Suteki would apply to a gorgeous female, a situation which is extremely nice, or something very touching such as falling in love.
"Suteki da ne?" (Beautiful, isn't it?)