Śeṣabhūtan — Wholly Belonging to Bhagavān
Śeṣabhūtan (Sanskrit: śeṣa = remainder / that which exists for another + bhūta = become / being) names the jīva in its true positive identity: one whose entire existence consists in belonging to Bhagavān. The term is not merely an abstract classification but an expression of the jīva's deepest ontological reality in Visiṣṭādvaita theology.
In Rāmānuja's metaphysics, the relationship between Bhagavān and the jīva is one of śeṣa-śeṣī — the jīva is the śeṣa (that which exists to serve and exist for another) and Bhagavān is the Śeṣī (the master and sustainer who owns the śeṣa). This is not a relationship of subordination in the negative sense, but the very constitution of the jīva's being. Just as light fulfils itself in shining, so too the jīva fulfils itself precisely in existing for the pleasure of the Lord (Bhagavat prītyartham).
Where śeṣatva names the abstract quality of this belonging, Śeṣabhūtan names the jīva that has become (bhūtan) fully what it truly is. In the bound state (baddha avasthā), the jīva forgets its śeṣatva and falsely assumes svātantrya (independence), leading to repeated births in saṃsāra. The process of jñāna and prapatti consists in the gradual or sudden recognition that one has always been and remains Śeṣabhūtan — and that this is not a loss of identity but its fulfilment.
Piḷḷai Lokācārya in Śrī Vachana Bhūṣaṇam explains that even the liberated jīva (mukta) in Śrī Vaikuṇṭham is Śeṣabhūtan in the fullest sense — engaged eternally in kaiṅkaryam (loving service) that expresses this belonging. The Āzhvārs, most especially Nammāzhvār and Tirumazhisai Āzhvār, celebrate this state through the language of complete surrender of the self to the Lord.