They can actually cook.
Doumeki can cook: he always cooked for his grandfather, it was the one of the small things he could do. His own food is passable, he can make rice balls, miso soup, ramen and any other simple foods. Living at a temple, there are many visitors so he helps his family make the food. He requests foods from Watanuki to know how he feels. Watanuki (despite being excessively vocal) hardly tells anyone what he truly feels. As long as Watanuki complies with his ridiculous requests he knows; Watanuki actually cares.
Himawari can cook: her mother taught her years ago. She bought her lunches or made them herself. Her cooking is quite good, better than most girls' because she doesn't really go out much. She finds cooking lonely because whenever she did, the people she cooked with (except her mother) always got hurt. She doesn't want to hurt anyone. She knows how Watanuki feels about her, she feels it is the least she can do to let him vent his feelings through food or his energetic flailing; she knows it can never be.
Yuuko can cook: she has lived on her own for years and years. It is not surprising that she can cook. She used to eat simply to sustain her body, there was no pleasure in it and her cooking was sufficient. Her vices were drinking and smoking, to dull the pain. She finds herself drinking less and less... Once she tasted his cooking, her own in comparison tasted much like dust. She is in no way modest but Watanuki has magic in the kitchen that she finds more powerful than her own vast ones; he can make the people he loves happy.
A/N: Congratulate me on my fast update? Review?
+Andy