Pisces in the Navamsa brings Jupiter's mutable-water compassion into the D9's marriage domain, and this placement — like Sagittarius, ruled by the same great benefic — is generally read favorably, though its expression is dreamier and more inward than Sagittarius's outward, philosophical expansiveness.
A spouse indicated here tends to be gentle, imaginative, and empathetic, often with a genuine spiritual, artistic, or compassionate streak, and the union itself is frequently described in classical terms as carrying a devotional quality — a bond that feels, to those in it, touched by something beyond ordinary partnership.
Pisces's own diffuseness is the traditional caution: the same idealism that gives this placement its tenderness can also blur clear-eyed judgment about a partner's real flaws, or invite avoidance of the marriage's practical, unglamorous demands. The lesson is keeping the union's genuine compassion tethered to honesty rather than letting it drift into wishful idealization.