https://www.scconline.com/blog/post/2018/09/21/slightest-penetration-of-whatever-degree-is-sine-qua-non-to-attract-provision-of-section-376-ipc-absence-thereof-regarded-as-fondling-tripura-high-court/
Slightest penetration, of whatever degree, is sine qua non to attract provision of Section 376 IPC; absence thereof regarded as ‘fondling’: Tripura High Court