The title comes from the abstract of an article[1] analysing why Biotin (vitamin B7) is such a strong and effective binder to proteins, with a free energy of (non-covalent) binding approaching 21 kcal/mol. The author argues that an accumulation of both CH-π and CH-O together with more classical hydrogen bonds and augmented by a sulfur centered hydrogen bond, oxyanion holes and water solvation, accounts for this large binding energy. 
References
- D.B. McConnell, "Biotin’s Lessons in Drug Design", Journal of Medicinal Chemistry, vol. 64, pp. 16319-16327, 2021. http://dx.doi.org/10.1021/acs.jmedchem.1c00975