Wikipedia
refers to a brief glimpse of a woman's underwear. The term carries risqué connotations similar to the word 'upskirt' in English usage. The word is a portmanteau of and chira, the Japanese sound symbolism representing a glance or glimpse. It differs from the more general term "upskirt" in that panchira specifies the presence of underpants (the absence of which would more accurately be described as ノーパン; nōpan).
In anime and manga, panchira usually refers to a panty-shot, a visual convention used extensively by Japanese artists and animators since the early sixties. According to Japanese sources, the convention probably started with Machiko Hasegawa's popular comic strip Sazae-san, whose character designs for Wakame Isono incorporated an improbably brief hemline. The practice was later transferred to animation when Osamu Tezuka's Astro Boy was adapted for television in 1963. Confined mainly to harmless children's series throughout the remainder of the decade, panchira took on more overtly fetishistic elements during the early seventies. From that point on, panchira became linked with sexual humor such as the kind found in many comedy oriented shōnen manga.
The word Panchira is similar to panty peek in English. In some Spanish-speaking countries, Fotografiando is sometimes used to let a woman know she is showing someone her underwear (as in ¡Estás fotografiando!-You are photographing!)