romance

Umi's romance life in the manga is very ambiguous compared to Hikaru and Fuu. There has always been a debate between two people where romance blooms with Umi. Watch out for spoilers.

ascot & umi

It is clearly stated in the manga twice that Ascot likes Umi. The first time, Caldina shouts out that Ascot used his will to transform his body into a tall young man for Umi. The second time, Ascot himself asks Umi if she has a boyfriend. In both cases, Umi is totally clueless (either that or she's rather good at hiding her feelings). It is unknown if Umi reciprocates her feelings towards Ascot. Mokona also later pairs up Umi and Ascot in the flying (conveniently a 2-seater) contraption, where Fuu and Ferio are in another ship and Hikaru and Mokona are in another.

clef & umi

In the middle of the night, Umi goes in search of Clef. She apologizes to him for being so mean when they first met because she did not understand how the Pillar system worked. She pours out her feelings on how she felt in the final battle against Zagato and Emeraude. Clef takes her hand and comforts her. Umi says thank you (and the background becomes dreamy with flowers). So I suppose one can say that Umi has feelings towards Clef and vice-versa, although this is the only scene throughout the manga where Clef and Umi are alone together.