sachiko shirayuki, original, highres, 1girl, areola slip, arrow (symbol), black hair, black nails, book, breasts, brown eyes, brown sweater, closed mouth, clothes lift, couch, english text, fertilization, fetus, fingernails, glasses, heart, indoors, interlocked mars and venus symbols, large breasts, long fingernails, looking at viewer, lying, mars symbol, multicolored hair, on back, on couch, open book, ovum, round eyewear, sex ed, sleeves past wrists, solo, sperm cell, sweater, sweater lift, two-tone hair, underboob, venus symbol, white hair