The comitative ending is -ne in the plural. Singular forms do not exist, but plural forms are always used no matter, if the meaning is singular or plural.
The comitative plural is formed using the strong-grade plural stem. The comitative ending is added directly to this stem. In addition, nouns always require a possessive suffix. The possessive suffixes are -ni 'my', -si 'your' (sg), -en/-nsa 'his, her, its, their', -mme 'our', and -nne 'your' (pl).