Have you heard of W-sitting? It's a specific sitting position in which you sit on your bottom while your legs are splayed out sideways. When viewed from above, the legs form a W shape, hence the name. This position is normally adopted by children as they tend to be more flexible. Not only is it adorable, but it also adds stability to their cores, helping them to stay upright more easily.
Yuuki (from Sword Art Online) certainly looks relaxed as she plays games on her bed, doesn't she?
Having so many amazing pieces of art below definitely counts as a "W" in our books.