This aspect of our oha mmuo comes from our affiliation with marine entities, and our affiliation with them comes from the belief that our consciousness was already in existence before reincarnation, hence, the popular Igbo saying “Kedu ebe isi bia uwa”. 
Ndi-Mmiri is a compound word for various water elements which include; Di/Nwunye Mmiri “Spiritual Spouse”, Ndi-Otu Mmiri “ Soul Group”, Okoro na Agboho mmiri, Umuaka Mmiri, Ezenwoke na Ezenwanyi mmiri and the primordial force that owns the water, thus, Nne/Nna Mmiri. Our affiliations with ndi-mmiri revolve particularly between our spiritual spouse and Otu mmiri, those we share a soul tie.
But, during the performance of water rituals, we acknowledge all these other entities and accord them a share of our sacrificial items as part of this cosmic water collective.
Our performance of water rituals is dependent on the exact force that is making a certain demand but generally, via our cosmology, we are obligated to perform; Ikwa ibu mmiri – the gathering of different sacrificial items and taking them to our mmiri-chi/mmiri-uwa.
We also perform, Ikwa Ibu ndi Otu- this particular ritual is dedicated to those we share a soul tie with and finally, Ikwu ngo mmiri- an intending groom does this for his intending bride, it borderline revolves around you seeking permission and informing her spirit spouse and yours of an intending marriage. 
The idea of Ikwu Ngor Mmiri, shares the same lifeline, with the perception of existence before reincarnation, hence, it is believed that the union between the spirit spouse and the living partner, has always existed before this marriage that is about to happen, and upon the death of the living partner, they would return to their spirit spouse.
Finally, the ritual of Ikpe Ire Oma is an occasional ritual, performed when one sees him/herself, in a situation that incapacitates their health/financials, especially, when there is an intended ritual to perform but the capacity to carry them is lacking, hence, this ritual would be temporarily carried out, until, the situation is remedied & the individual can now carry out the proposed ritual.
•Culled from Odinala Group.
Ndi-Mmiri
