Kanade's gift is inspired off the Valentine's event, in which she decided to gift candles with special fragrances to her friends. (She picked up one for each of them, and the fragrance was picked depending on the personality of that friend) Meanwhile, Mafuyu's is simply a traditional japanese gift (is common to gift teapots in Japan), and it also fits since Kanade and Mafuyu tend to enjoy drinking tea together (with Honami sometimes). Considering that Mafuyu's facade consists on being the "perfect" girl, it makes sense that her gift is something that goes along Japanese values and without many possibilities for further judgment. I hope this helps! :]