demons get if killed by Krishna

 
When the demons achieve sāyujya-mukti and leave behind their sinful activities, they are blessed by Viṣṇu's garland, which is red like blood.
As for rudhira, or the blood of Lord Visnu, since there is no possibility of severing Lord Visnu's head from His body, there is no question of blood. But the garland that decorates Visnu's body is as red as blood. When the demons achieve sayujya-mukti and leave behind their sinful activities, they are blessed by Visnu's garland, which is red like blood. After attaining sayujya-mukti, the demons are sometimes promoted to the Vaikuntha world, where they receive the reward of the Lord's garland prasada.    (More...)

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