For as long as dark corners still "lurk" in our heart?

Here are a few constatations, which, if convincing, could add to your information.

This verb can be used with abstract subjects since it is used widely with the word "danger" and other words representing abstract concepts : "danger lurking, the danger that lurks".

ref. 1, 2013 Yet when one asks women about danger, their fears translate into concerns about the danger lurking in the physical environment: car parks, public stairwells and public transport, for instance, are typically named by women as dangerous

ref. 2, 1975 Who Knows what Lurks in the Mind of a Child?

ref. 3, 2007 That is, there is to be no information that lurks inaccessible within the system. Pieces of information not to be displayed for security reasons (such as passwords, hashed data, or data encrypted using a key unknown to the user) or for other valid

As "dark corner" in this context can't be anything else than an abstract concept, it should be justified to use the verb "to lurk", although I must admit, the analogical connection that is made with the concrete concept of a dark corner in a building can make the combination appear strange; nevertheless, all that can be retained is the abstract concept, which, as a metaphorical rendering, is something spiritual removed from the common run of the spiritual activity a human being is subject to, as in a house a dark corner that, in order to be a dark corner, can't be where the life of the house is concentrated.

It is true that inanimates are not often used as subjects. Here is an instance though where the inanimate, if "a world" can be so called, is used as subject.

ref. 4, 2001 Beneath the glossy surface of official design lurks a dark and strange world driven by real human needs.

Here below is another one, more convincing, since the degree to which light can be endowed with "life" is not as great as for a world.

ref. 5, 2015 Girl in the Dark - Page 137

The use of the word "lurk" must however be taken as metaphorical.

In this next reference can be found used as subject of "lurk" the ultimate inanimate in a gradation from the animate to the inanimate.

ref. 6, 2013 Younger Next Week: Your Ultimate Rx to Reverse the Clock, ...

Below can be found a confirmation of your understanding that "lurk" is hardly used with inanimates; this characteristic is so essential that it confers to the word the property of giving life to the inanimate.

ref. 7, 2000 Consider these two sentences:
The table is stationary.
The table lurks stationary.
Notice how "lurks" as a metaphor doesn't just animate the table, it animates the writer.

Follows now a figurative use of the verb where the subject is perfect inanimates.

ref. 8, 2012 With oil and gas reserves thought to lurk beneath those waters, the stakes will rise as China's economy grows ever more thirsty for growth-sustaining energy sources.

ref. 9, 2011 The objective of this paper is to warn and alert social networking users of the dangers that lurk on popular sites such

ref. 10, 2010 Demons and other adversaries lurk at every turn in the road, ready to ambush.