彼はこのところふとってきている。

he; him; his; boyfriend

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

this (something or someone close to the speaker (including the speaker), or ideas expressed by the speaker)

place; spot; scene; site; address; district; area; locality; one's house; point; part; space; room; whereupon; as a result; about to; on the verge of; was just doing; was in the process of doing; have just done; just finished doing

to grow fat (stout, plump); to become fat; to gain weight