Japanese illustrator Maori Sakai has created a bunch of adorable animated GIFs with seasonal themes.
The illustrations are vignettes in soft colours. I think they have an almost vintage appeal; the detail and hatching almost mimics the effect of engraved printing but with a softer touch. I also really like the hand-lettered writing used in many of the drawings.
They perfectly capture the feeling of each season — the dog playing in a pile of leaves and the couple surrounded by falling leaves for autumn, an old-fashioned lemonade machine and a boat on the ocean for summer, and a series of several designs with bouquets, each titled Flower For You, for spring.