Wrong way to do it

This plugin does not produce a true shortcode. It introduces non-standard, ambiguous markup — single open/close brackets around a single letter. This causes problems for excerpts and is indistinguishable from a commonly used way to indicate alterations in a quotation.

Additionally, the plugin looks for each letter of the Latin alphabet and applies its own markup and CSS but without providing unique classes for each letter. This is useless for non-Latin alphabets, it’s useless if you want to create custom styles for each letter, and it’s useless in every other respect as well.