Lirin is the daughter of the Ox-King Gyumaoh by his mistress Gyokumen Koushou in the manga and anime Saiyuki and also Kougaiji's half-sister.

Her older half-brother, Kougaiji, loves her despite the fact she is a constant reminder of his father's infidelity to his wife and Kou's mother, Ratsetsunyo. In personality, Lirin is uncannily alike to Son Goku, the heretical monkey from the Sanzo Ikkou. She is happy-go-lucky, always smiling; but despite her comparative youth she is still a powerful fighter, albeit with very large breasts.

In Saiyuki Reload (manga version), she was nearly experimented upon by Ni Jian Yi. However, Kougaiji managed to free her. The half-siblings, together with the ever faithful Dokugakuji and Yaone, set out on their own journey to wrestle the sutra from the Sanzo Ikkou.

(Source: Saiyuki Wiki)