Good afternoon, Anna!
Tights pulled on skates are a fairly common phenomenon in women's single and pair figure skating. There are several explanations for this.
Because they are produced by themselves, but the skater can always choose the type of tights that suits him best for the suit / color of the boots (if you need to hide it).
There are several types of tights: some, as in ordinary stores, but made of dense material, others with "boot covers", as in the picture.
And most importantly, how they do it without touching the blade .. (c)
It is impossible to touch the blades, tights of this type do not have fabric on the foot and heel, and are “applied” to the boot, securing the fabric under the hooks / buttons / Velcro.
The presence of a cover on the skate's boot, sometimes combined with tights or suit trousers, is a necessary protection against fastening elements and laces. Including to avoid unlacing the boot, hitting the lace, or vice versa, so that the athlete or his partner does not get caught on the hooks by the suit and hair.