From the designer, Asuka Ozumi:

This is a pattern for beginners who are tired of garter stitch
or plain stockinette. It’s also a good starting point for using 40
cm circulars.

Materials
You can use any yarn or needles that gives you a gauge you
like.

Lilac: Lana Gatto Scandinavia, 1 skein; 5 mm 40 cm circular
needles.

Pink: Alma Irrestringibile Lana Golf, 1.5 skeins, double
stranded; 4 mm 40 cm circular needles.