
When a yukkuri's stupidity, overconfidence, superiority complex, and/or limited experience causes them to hold a skewed view of the world that's heavily biased towards themselves. Shitheads (and by that extension deibus and wasa reimus) are naturally delusional creatures though not all delusional yukkuri are shitheads.
A lot of koyukkuris are born delusional but unless they're truly shitheaded these delusions can usually be corrected with good parenting. Conversely a relatively humble or level-headed yukkuri can turn delusional if they're too spoiled which is a particularly common mistake among inexperienced pet owners.
These skewed views vary but the some of the most common examples include:
Usually followed by reality hits hard or too dumb to live