Demonstrative Pronouns (dieser, jener)
How do "dieser" (this/these) and "jener" (that/those) decline?
They decline exactly like definite articles (der, die, das) but are used as adjectives or pronouns.
Example
Ich mag dieses Buch. (I like this book - accusative neuter)
Diese Frau ist meine Tante. (This woman is my aunt - nominative feminine)
Gib mir jenen Stift. (Give me that pen - accusative masculine)