Sri Nrisimha Dev has two dispositions. He is terrible with non-devotees, but with devotees, He is very affectionate and caring.
The following verse from the agamas is quoted as evidence by Sree Sridhara Swami in his commentary on Srimad-Bhagavatam 7.9.1:
ugro ’py anugra evayam sva-bhaktanam nri-kesari
kesariva sva-potanam anyesham ugra-vikramah
(Caitanya-caritamrita, Madhya 8.6)
“Although very ferocious, the lioness is very kind to her cubs. Similarly, although very ferocious to non-devotees like Hiranyakasipu, Lord Nrisimha Dev is very affectionate and kind to devotees like Prahlada Maharaja.” (Srila Bhakti Vinod Thakur)
This expresses thoroughly the glories of Sri Nrisimha Dev’s unique mercy.
Devotion to Sri Nrisimha Dev enhances bhakti and destroys uncongenial adverse motivations.