Śrī — The Auspicious One
Lakṣmī is called Śrī — she is auspiciousness itself. Where she resides, there is fullness, well-being, and the Lord's grace. The very name Śrīman Nārāyaṇa honors her primacy: Nārāyaṇa is always accompanied by Śrī. The opening of the Divya Prabandham with the Tiruppallāṇḍu and the invocation Śrīmate in many mantras reflects this centrality.
Purushakāra — The Intercessor
In Sri Vaishnava theology, Lakṣmī performs the unique role of purushakāra — the one who places the devotee before the Lord and commends them to his grace. Just as a petitioner needs an intermediary to approach a king, the jīva (individual soul) needs Pirāṭṭi's intercession. She says to the Lord, in effect: "These are your people. Despite their faults, receive them."
This makes her not merely a divine consort but an integral part of the means (upāya) itself. The Dvaya mantra invokes both Śrī and Nārāyaṇa together — surrender is offered śrīmate nārāyaṇāya — to Nārāyaṇa who is with Śrī.
Never Apart
Visiṣṭādvaita holds that Lakṣmī and Nārāyaṇa are eternally inseparable (nitya-yoga). She is not created; she is eternal. She is not bound by karma; she is ever-liberated. She participates in all his vibhava (cosmic manifestations) and is present in the arcā (deity form) of every Divya Desam. In the Āzhvār literature, she is Periya Pirāṭṭi — the Great Lady.