Nobody's Baby But Mine by Susan Elizabeth Phillips

A brilliant, eccentric single woman, convinced that her uncommon intellect and upbringing will doom her child to the same lonely life, decides she must deliberately find an uncomplicated, ‘average’ man to father a baby; what starts as a calculated plan to seduce, conceive, and walk away turns into a raucous battle of wills filled with comic misunderstandings, prickly chemistry, and unexpected tenderness as both protagonists are forced to rethink family, responsibility, and what it means to love someone beyond a carefully made plan.

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