That inauspicious Karma-prakṛti (type of Karma), which has inauspicious intensity (of fruition), which results in melancholy, e.g., Asātavedanīya (Karma, responsible for the experience of feeling of suffering), Nīcagotra (status-determining Karma qua low status) etc...
nāsti śubho raso yāsu tā aśubhāḥ.
(Kapra p.34)