Mercury opposite Pluto (orb 1.8°) puts the two planets face to face, with visible back-and-forth or tension. The orb is very tight; this describes a stable character pattern more than a passing reaction.
Here, Mercury in Pisces in House 7 brings intellect, language, thought, and technique into House 7 (relationship, confrontation, and the mirror of others), with Pisces style (imagination, faith, compassion, dream, and permeability); Pluto in Virgo in House 1 brings crisis, power, survival, and regeneration into House 1 (presence, body, and the way experience is entered), with Virgo style (precision, method, usefulness, and attention to detail).
Concrete conflict: this aspect sets intellect opposite Pluto: speech, analysis, or information can conflict with secrecy, power, crisis, or control. Visible angle: Mercury near the Descendant (orb 5.3°) and Pluto near the Rising sign (orb 3.4°) touch angles; this aspect is easier to notice through direct relationships, partners, opponents, and the way others are met; also through first impression, body language, reflexes, and entry style. The house conflict is between House 7 (relationship, confrontation, and the mirror of others) and House 1 (presence, body, and the way experience is entered); pressure in one field tends to reactivate the other.