「Horse with door to genitals, buttocks」using elements that emphasizes one difference between a horse and an ass. Horses spook easily, asses do not, horses are trusting if it feels good while asses doubt and are very cautious:
「Donkeys are not like horses. They differ physically, mentally and emotionally. Donkeys are more stoical in their behaviour and tend to startle less than horses. Compared to horses, donkeys show limited fear response to novel situations and this can be mistaken for stubbornness rather than fear. Teaching a donkey requires a different [mindset than] teaching a horse. They cannot be rushed into doing something they don't want to do!」
[ https://www.ed.ac.uk/polopoly_fs/1.21412!/fileManager/donkey%20fact%20sheet.pdf 2013-01-07 ]
On the other hand, a horse may not care what you do to its genitals or buttocks, just as long as you do not spook it while doing so. Note that this glyph may have contributed to a buttocks being referred to as an ass in English.
Without a doubt, the Irish also have knowledge of their own to pass along in these trying times:「Masturbation will not spread coronavirus, especially if you wash your hands (and any sex toys) with soap and water for at least 20 seconds before and after.」Nonetheless and regrettably, unlike in dynastic China, it must be undertaken alone to truly be a preventative countermeasure but still achieve the desired result with some degree of safety.
[ https://www.sexualwellbeing.ie/sexual-health/sex-and-coronavirus/ 2020-03-31 ]
The Dutch, too have the same solution—it seems masturbation has become mainstream in the media the world over due to the coronavirus (it has always been 'the main stream' in reality, albeit covertly for most folks):
「'Don't have sex with your partner if they have been isolated because of (suspected) coronavirus infection,' the RVIM says. 'Sex with yourself or with others at a distance is possible (think of telling erotic stories, masturbating together).'」
[ https://www.theguardian.com/world/2020/may/15/dutch-official-advice-to-single-people-find-a-sex-buddy-for-lockdown-coronavirus 2020-05-16 ]
Needless to point out perhaps, but Chinese shamans from antiquity hit upon the same solution as a pandemic preventative countermeasure, honed for ultimate client satisfaction by utilizing naked females with no-longer-integrated feet as masturbatory sex buddies available for short-term rental with erotic visualization of live prepubescent female genitalia engaging in autoerotic stimulation herself, as a solution to the same problem facing us now, but in pre-Internet days.

External source definitions …excluding politically incorrect concepts and other meanings deemed offensive today; may include extended definitions, euphemisms, and mnemonics)
Japanese EDRDG: ass, donkey
Unihan extended: an ass; a donkey