plural-2
Explanation
This comic is a linguistics and tech nerd joke about pluralization rules. It begins with a simple office scenario: one person says they will send "the GIFs." A pedantic coworker objects, arguing that the plural of GIF files should be "gives" -- as if the file extension follows the same irregular English pluralization pattern as "shelf/shelves" or "elf/elves."
The joke escalates as the pedant pushes her absurd pluralization system further. She insists that the plural of .man files should be ".men" (like man/men), and when the other character starts to push back, she goes even further: ".javae" (as if Java follows Latin pluralization), ".icoi" (as if .ico follows Greek/Italian rules), "a herd of docxen" (applying the archaic English ox/oxen pattern to .docx), and finally "txticles" as the plural of .txt files (modeled on "testicles" or perhaps "ventricle/ventricles").
The humor works because it takes a real linguistic pedantry that many people engage in (the "GIF vs JIF" pronunciation debate, arguments about correct plurals) and pushes it to its logical extreme by applying natural-language pluralization rules to file extensions, which are obviously arbitrary technical abbreviations that have no business following any linguistic rules at all. The other character's bewildered "I can't tell if you're serious" perfectly captures the experience of dealing with someone whose pedantry has crossed over into performance art.