Thirsty for Love (2001)

Blurb:
Yuka loves the passionate Orie, the arrogant Tatsumi and the painfully honest Suguru. All are different, but each is loved deeply and sincerely. One of the boys doesn’t know that his girlfriend is cheating on him, another doesn’t seem to care that he shares his girl with others, while one turns a blind eye to the situation. So what happens if you take away their common denominator? Secrets and lies are unearthed and, with Yuka’s sudden passing, the three boys are left feeling empty. But with Yuka gone, who will fill their thirst for love?

Source: www.anisearch.com/manga/2209