S. R. Faruqi:

It's a verse in Mir's special style. On the one hand he's mentioned the beloved's tyranny, on the other hand he's also poked fun at himself. Thus in the theme, instead of pain and disappointment he's created somewhat of an air of cheerfulness: 'Run along, my friend, and pursue your passion!'.

He's created this freshness in the theme by juxtaposing to the word 'blood-drinker' the word 'colorfulness'. Then, there's also the pleasure that this spirit-exhausting experience occurred when he met the beloved. Thus in principle this is a verse not of separation, but rather of meeting; and this meeting has occurred in the manner of an experience of everyday life. In this way the experience of passion (which has been presented in a maximally hyperbolic style) has become a part of ordinary life and comes before us as such.

On the one hand, Mir composes verses that present the experience of passion in maximally frightening and spirit-exhausting form, as apart from the ordinary world, but nevertheless near to human life. For example, from the third divan:

{1109,11}.

And on the other hand, he composes verses in which the experience of passion seems to be purely terrifying and very far from ordinary life; for example, from the second divan:

{711,5}.

Then, he composes verses like the present one, in which the heart-devastating experience of passion has been presented with cheerfulness. The variety of the experience of passion in Mir's poetry is greater than in the poetry of any other Urdu poet, and in Persian only Hafiz and, to some extent, Khusrau can compare with him. For detailed discussion, see the introduction to SSA, volume 1.

FWP:

SETS
MOTIFS
NAMES
TERMS

The intransitive grammar gives the verse a particularly detached quality, like a report. The first-person lover whose experience of passion is being reported remains almost invisible. The 'colorfulness' of passion turns out to be generated from the lover's own blood, and the beloved is like a dangerous beast, a 'man-eater' of some kind hitherto unknown to the reporter.

The phrasing of the second line leaves open the question of whether the lover had simply never experienced passion before, or whether he had had dealings with other beloveds, but none of them had been 'blood-drinkers' before.

Note for grammar fans: In the first line, nowadays we'd of course expect milne par .