A large wood sculpture depicting Ajarukula Nepal, 16th century | 尼泊爾 十六世紀 木雕羊頭神屋樑

The corner struts are called Kunsala in Newari meaning a horse in the corner. The function of corner struts is to keep the roof stretched and balanced. 

Usually the corner struts would be longer than other struts. Heraldic lions and griffons powerful creatures employed not only as functional supports of the heavy roof corners but also as spiritual defenders of the temples. Usually there would be four spiritual animals carved on these struts comprised of Sinha(lion), Sardula(griffons), Ajarukula(goat headed demon) and Maahaanaaga(serpent headed, actually an aquatic demon).

For reference: 

- Adalbert J. Gail, Temples in Nepal (Band I) - Ikonographie hinduistischer Pagoden in Patan Kathmandutal, Akademische Druck - u. Verlagsanstalt Graz/Austria, 1984. Image of a similar roofstrut is found in Tafel XIX, fig. 3.

- Ernst und rose Leonore Waldschmidt, Nepal, Kunst aus dem Königreich im Himalaya, Verlag Aurel Bongers, Recklinghausen, 1967, fig. 62a +62b