January 23, 2014, 05:29 pm UTC: A nonny asked whether anyone else had played the free phone/tablet game Alpaca Evolution. Twelve minutes later, another nonny replied: "Could have trigger warned me for the smoking. Thanks, jerk."

The image in question:

Smoking alpaca

(Note that the image in the Tumblr post linked by the OP did not contain any smoking whatsoever.)

Someone else wondered when smoking had come to require a trigger warning, and the second nonny sniped,

When we figured out that it causes lung cancer.
Geez, I'm trying to quit. Seeing an alpaca smoking doesn't help.

And thus commenced a huge wank in which troll!nonny kept hooking other nonnies quite ably and throwing out more bait. Over the next four hours, the comments kept piling up, until troll!nonny tipped their hand with "Thank you for encouraging me to contract lung cancer" and, even more so, when chided for having a lack of "willpower," replied, Wonder what leafing would say about that." (Reference.) That thread got frozen under the That Much of an Asshole rule.

So did the one beginning with, "I assume you've never had anybody die from lung cancer in your family." Backup Sunny informed troll!nonny, "Emphysema, thanks (though I am not the anon you replied to). It was horrible and took years," and reaffirmed that meme is a CNTW experience.

This wank also featured protracted discussion over whether the sight of someone, or something, smoking could properly be called a "trigger" for a person trying to quit. More amusingly, there was this: "He has alpaca-day habit."

"Smoking Alpaca" became an instant meme meme:

Troll!nonny made an attempt to reignite (heh) the wank on February 4, in another TYWSU thread. The earlier context having been rape wank that segued into teetotaler wank, the attempt was somewhat anticlimactic.

And in April 2014, troll!nonny confessed (in a "which nonnie are you" type thread) to being not only Smoking Alpaca nonnie, but also Cat Soulbond Nonny, to great acclaim.